To the right honourable and right noble Prime Minister of Funny Looking Glasses[1], salutation I extend.

Some beginners try to copy their native verb forms directly into Esperanto. Something along these lines:

“I smoke” is “Mi fumas”. Therefore, “I am smoking” must be different. Therefore, it is “Mi estas fumanta”.
Wrong. “I am smoking” is “Mi fumas”.

“I smoked” is “Mi fumis.”. Therefore, “I have smoked” must be different. Therefore, it is “Mi estas fuminta”.
Wrong. “I have smoked” is “Mi fumis”.

Not only beginners, but also quite proficient Esperanto speakers, tend to have problems with the tenselessness of the -us and -u forms. Something along these lines:

“If I went to the gym today, I would train a lot.” is “Se mi irus hodiaŭ en la ekzercejon, mi ekzerciĝus multe.” Therefore, “If I had gone to the gym yesterday, I would have trained a lot” must be different. Therefore, it is “Se mi estus irinta (irintus) hieraŭ en la ekzercejon, mi estus ekzerciĝinta (ekzerciĝintus) multe.”
Wrong again. “If I had gone to the gym yesterday, I would have trained a lot” is “Se mi irus hieraŭ en la ekzercejon, mi ekzerciĝus multe”.

Oh wait, we also need a 1-to-1 translation for “should” and “could”. Eezy-peezy: devus and povus.
“I should go” is therefore “Mi devus iri” and “I could go” is therefore “Mi povus iri”.
Wrong again. “mi devus iri (se io okazus)” means “I would need to go (if something happened)” and “mi povus iri (se mi havus gambojn)” means “I would be able to go (if I had legs).
“I should go” is in most cases just “Mi iru”.

And don’t get me started about the “devintus/povintus” faction.

Everytime someone writes “devintus” or “povintus”, they tear down the gossamer veil between our world and the nether realms where HE-Who-Waits-Behind-The-Wall feasts and gores on the tears of ravaged minds.

Mi povintus iri, se mi sciintus pri tio. V̵̜̀į̵͊ ̷̖̿ḋ̸̞ȅ̸͉v̷̡̑i̴͇̋n̸̨̈t̸̢̀ṳ̴͝s̴̪̍ ̶̮͊s̶̝̈́p̷̧̓e̵͑͜k̵̖̂t̷̯̅i̵̫̽ ̴̝͊t̴̥͝ĭ̸̘u̷̝͘ṇ̴̈́ ̸̰̽f̵̤̄i̷͕̒l̶͉̓m̴͈͆o̷̺͝n̸͈̽.̴̙̓ Ņ̵̜͓̞͙̠͎̼̞̲́̑̀̒̒͝͝ͅi̴̛̘̥͓̳̙̜̜͓͍̐̐̈́̔̈̎̀̕͝͠ ̸̬̻̖̰̰̝̜̯̼͙̑̀́̾̓́͂͝p̴͇̫̠̺̙͊͆̊̅̕̚ǫ̸͈͎͍̈̈́͐͋͒̒͑̓̈̒̌͗v̴͇͇̼͍̀͛̑̈̏͋̇̀̀̍̏̉̓̚͝͝i̴̳͍̺̜̓̿͐̄̓̓́̄̈̽͑̽̾̈́͘̚n̷̩͙͎̹͍̅̓̂͂͂̍̈́́̌͐͌̚͜ţ̶̘̿̂̍u̴̢͓̝͉̤̘̺̦͔̰̜̭̞͑͌ͅs̶̡̺̳̠͇̪̟͓̬̞͙͙̈́̈́̌̑̌̾͛́̄̀͑̈͘ ̵̨̨̨̣̝͔̫͇̦̩͈̦̜̟͊͛̾̒͗͒̀͆̚͠ͅp̵̧̧̛̥̩̜̥͎̞̦͈͉̌̾̇̉̋̆̌̾̊ͅͅͅä̴͈̻͚̲̺̫̬̤͚́̋́̓̀͐̈́̏̀͒͆̊͘͜͝͠ŗ̸̧̨̛̻͖͔͎̜̮̞̯̯͙̱̯̖͐͂͋̂́̆ò̴͉͍̝̱͚̜̘͈͉̳͓͑̀͋̓̇̑̈́̿̀͜ļ̴̢̞̙͔͖̑̌͘͜͠͠i̸̡̱̩̦̖̹̔̅ ̶̺̘͍͓̮̺͛̿̽E̶̙̟͇̬͕̜̤͈̾s̴̨̛͔͉̙̘̣̟̯͇͖̦̮̚ṗ̶̥͐́̑̈́ę̴̮̻̗̭̭̙͎̯͔̣̙̦̈̋̄̆̅̉̋͑̀͋͘r̷̡͖͖͖͓̪̜̥̄̈́́́̋̈́́̒͊̈́̋a̶̦̭̹͊̒̃̈́̽͝ņ̸̝͎͍̤̘̩͚̯̗͉͖̰̝̉͌̾̈͌̒͑̄̓̑͌͂̓̓̇̓t̵̛̩̣̩͓͚̏͌͋͛̅͝ͅơ̷̧̡̡̢͕̪̺̘̩̻̖͚͙̓́͂̓̄͐̿͆̈̆̉͠n̷̡̲̳̫̠͍̣̞̼̉͐̏̒̎͌̇̓̽̉͜,̶̨̡̜̍̾̓́̂̿̾̐̆͝ ̵̡̛͓̺͍̬̟̞̭̼͔̬͕̲̤̦́̒̄͋̑́̏͋̍́̓̇͑͠͠s̸͈̙̮̮̝͔͐̀̌̃̕ë̴̛̥̯̳̮̭̟͚͈̳́̐̽̎̔͌̓̌̾̕̚͝͝͠ͅ ̵̭͖́̃̎̾̀͐̕͜͠n̶̞̩͙͉͛̌̇͊́̊̔͠͝į̸̛̖̜̼̘͎̗̪͖̼͔͌̆̑̅͠ ̷̢̧̬͉̭̼̣̤̼͔̺̳̆̔̀̎̔͑̊̊̏͊̈́́͌n̴͕̦̖͉͙̦̟̟̄̅͆͐̃̌́̌̔́͐̍͘͘ͅẹ̸̛͗̋̇̄̇͝ ̷͈̏̓̍̂ď̶̛̲̳͌̀͌̽̂̓͛̈́̋̿͠͠͠e̵̡̳̖̞̻̻̣̍̓̒̎̕͠v̸̡̨̧̡̱̟̫̜̹̜͓͓̟̳̯͑̄̍͑͌i̴̛͕̤͉̳̹̮̬̣͛̔͊͐̀̈́͒̃̽́̈́̿̐̕͝n̸͓͒͂̏̓͑̏͂͝ẗ̷̢̨͇̥̟̠̜̼̞͖͇͍́̾͗̓̉̎̓̕ͅų̶̟̜͈̟̰̠͉̿̀́̔̓̈́͛̄̈́͋̍̉̽͠s̶̨̫̄̆̿̿͆͆̄͂̈́̀͂̚̚͝͠ ̴̱̲̠͖̹̩̼̳̜̱̹̔p̷̨̡̨̛̲̼̩̦̟͔̫̗̲̤̤͒̉͌̂̌̕͝ȃ̴̺̬̥̳͎̲̓̈̈̃͝͝r̸͖͔̠̜̹̒̐̑͑̄̃̕͝õ̸̧̢̱͚̮̥͔̮̦̼̖̳͆̓̑̀̋̊̇́͌̄̚͘̚ͅl̴̩̞̝̰̤̃̈̀͋ͅḯ̸̫̔̅̽̆̀̕̕͝ ̷̞̩͙͕̘̳̫̹̩͎̮̞͉̿́̒̉̀̂̑̈͗͌̊̄͊́͘͜͝Ȩ̶̨͍̠̮̭̝̹̝̲̦̝̖̯̳̂s̶̜̬̫̉͋̀̆̿̂͂̈́͊̈̄̈́̕̕͠p̵̨̛̛̠̰̭͍͎͕̅̄͋̔͌̏̋͂́͆̈́͜e̶̢̨̥̬̗͒r̸̰͚̟̳̖̤̆̔̋̐́̑̀͆̆͘͜a̷̛̰͈̪̭͖͔̋̎͊̾̋̂̚͝n̴͉̠̪̾̈́̓͌͊͊̊͒͑̅̚ţ̶̞͙͈̬̤͚̱̠̭̗̪̥̤̖̇̍͆̔̀̀́̆̄̄̎͠i̸̡̼̥̜̮̭͈̠͇͆̂̎̓̉͒̊̆̀̐̌̽͘͝ņ̷̤̙͎̹̤̥̫̜̂̿̾͒́̒͂͐̌̄̒̑͊͘͠͝ţ̸͖̭̱̮̞̬͇̫̬̪͎̒̈́͑̒́͌͐̓͂̀́͑̓̚͜u̸̙̟̾̏s̶̛̛̩͙͚͍͕̼̺̺̱͗͌͌́̈̂́̉̉͜͠ǫ̶̢̜̬̳̬̦̥̭̫͚̱̐̄̒̌̓͜͠͝ͅn̵̩̘̖̤̪̖̭̜̬̜̎̅ͅ.̶̢̜̠̪̪͖̯͊̈́ ZALGO!

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[1] I mean (funny (looking glasses)) not ((funny looking) glasses).

nornen:
V̵̜̀į̵͊ ̷̖̿ḋ̸̞ȅ̸͉v̷̡̑i̴͇̋n̸̨̈t̸̢̀ṳ̴͝s̴̪̍ ̶̮͊s̶̝̈́p̷̧̓e̵͑͜k̵̖̂t̷̯̅i̵̫̽ ̴̝͊t̴̥͝ĭ̸̘u̷̝͘ṇ̴̈́ ̸̰̽f̵̤̄i̷͕̒l̶͉̓m̴͈͆o̷̺͝n̸͈̽.̴̙̓ Ņ̵̜͓̞͙̠͎̼̞̲́̑̀̒̒͝͝ͅi̴̛̘̥͓̳̙̜̜͓͍̐̐̈́̔̈̎̀̕͝͠ ̸̬̻̖̰̰̝̜̯̼͙̑̀́̾̓́͂͝p̴͇̫̠̺̙͊͆̊̅̕̚ǫ̸͈͎͍̈̈́͐͋͒̒͑̓̈̒̌͗v̴͇͇̼͍̀͛̑̈̏͋̇̀̀̍̏̉̓̚͝͝i̴̳͍̺̜̓̿͐̄̓̓́̄̈̽͑̽̾̈́͘̚n̷̩͙͎̹͍̅̓̂͂͂̍̈́́̌͐͌̚͜ţ̶̘̿̂̍u̴̢͓̝͉̤̘̺̦͔̰̜̭̞͑͌ͅs̶̡̺̳̠͇̪̟͓̬̞͙͙̈́̈́̌̑̌̾͛́̄̀͑̈͘ ̵̨̨̨̣̝͔̫͇̦̩͈̦̜̟͊͛̾̒͗͒̀͆̚͠ͅp̵̧̧̛̥̩̜̥͎̞̦͈͉̌̾̇̉̋̆̌̾̊ͅͅͅä̴͈̻͚̲̺̫̬̤͚́̋́̓̀͐̈́̏̀͒͆̊͘͜͝͠ŗ̸̧̨̛̻͖͔͎̜̮̞̯̯͙̱̯̖͐͂͋̂́̆ò̴͉͍̝̱͚̜̘͈͉̳͓͑̀͋̓̇̑̈́̿̀͜ļ̴̢̞̙͔͖̑̌͘͜͠͠i̸̡̱̩̦̖̹̔̅ ̶̺̘͍͓̮̺͛̿̽E̶̙̟͇̬͕̜̤͈̾s̴̨̛͔͉̙̘̣̟̯͇͖̦̮̚ṗ̶̥͐́̑̈́ę̴̮̻̗̭̭̙͎̯͔̣̙̦̈̋̄̆̅̉̋͑̀͋͘r̷̡͖͖͖͓̪̜̥̄̈́́́̋̈́́̒͊̈́̋a̶̦̭̹͊̒̃̈́̽͝ņ̸̝͎͍̤̘̩͚̯̗͉͖̰̝̉͌̾̈͌̒͑̄̓̑͌͂̓̓̇̓t̵̛̩̣̩͓͚̏͌͋͛̅͝ͅơ̷̧̡̡̢͕̪̺̘̩̻̖͚͙̓́͂̓̄͐̿͆̈̆̉͠n̷̡̲̳̫̠͍̣̞̼̉͐̏̒̎͌̇̓̽̉͜,̶̨̡̜̍̾̓́̂̿̾̐̆͝ ̵̡̛͓̺͍̬̟̞̭̼͔̬͕̲̤̦́̒̄͋̑́̏͋̍́̓̇͑͠͠s̸͈̙̮̮̝͔͐̀̌̃̕ë̴̛̥̯̳̮̭̟͚͈̳́̐̽̎̔͌̓̌̾̕̚͝͝͠ͅ ̵̭͖́̃̎̾̀͐̕͜͠n̶̞̩͙͉͛̌̇͊́̊̔͠͝į̸̛̖̜̼̘͎̗̪͖̼͔͌̆̑̅͠ ̷̢̧̬͉̭̼̣̤̼͔̺̳̆̔̀̎̔͑̊̊̏͊̈́́͌n̴͕̦̖͉͙̦̟̟̄̅͆͐̃̌́̌̔́͐̍͘͘ͅẹ̸̛͗̋̇̄̇͝ ̷͈̏̓̍̂ď̶̛̲̳͌̀͌̽̂̓͛̈́̋̿͠͠͠e̵̡̳̖̞̻̻̣̍̓̒̎̕͠v̸̡̨̧̡̱̟̫̜̹̜͓͓̟̳̯͑̄̍͑͌i̴̛͕̤͉̳̹̮̬̣͛̔͊͐̀̈́͒̃̽́̈́̿̐̕͝n̸͓͒͂̏̓͑̏͂͝ẗ̷̢̨͇̥̟̠̜̼̞͖͇͍́̾͗̓̉̎̓̕ͅų̶̟̜͈̟̰̠͉̿̀́̔̓̈́͛̄̈́͋̍̉̽͠s̶̨̫̄̆̿̿͆͆̄͂̈́̀͂̚̚͝͠ ̴̱̲̠͖̹̩̼̳̜̱̹̔p̷̨̡̨̛̲̼̩̦̟͔̫̗̲̤̤͒̉͌̂̌̕͝ȃ̴̺̬̥̳͎̲̓̈̈̃͝͝r̸͖͔̠̜̹̒̐̑͑̄̃̕͝õ̸̧̢̱͚̮̥͔̮̦̼̖̳͆̓̑̀̋̊̇́͌̄̚͘̚ͅl̴̩̞̝̰̤̃̈̀͋ͅḯ̸̫̔̅̽̆̀̕̕͝ ̷̞̩͙͕̘̳̫̹̩͎̮̞͉̿́̒̉̀̂̑̈͗͌̊̄͊́͘͜͝Ȩ̶̨͍̠̮̭̝̹̝̲̦̝̖̯̳̂s̶̜̬̫̉͋̀̆̿̂͂̈́͊̈̄̈́̕̕͠p̵̨̛̛̠̰̭͍͎͕̅̄͋̔͌̏̋͂́͆̈́͜e̶̢̨̥̬̗͒r̸̰͚̟̳̖̤̆̔̋̐́̑̀͆̆͘͜a̷̛̰͈̪̭͖͔̋̎͊̾̋̂̚͝n̴͉̠̪̾̈́̓͌͊͊̊͒͑̅̚ţ̶̞͙͈̬̤͚̱̠̭̗̪̥̤̖̇̍͆̔̀̀́̆̄̄̎͠i̸̡̼̥̜̮̭͈̠͇͆̂̎̓̉͒̊̆̀̐̌̽͘͝ņ̷̤̙͎̹̤̥̫̜̂̿̾͒́̒͂͐̌̄̒̑͊͘͠͝ţ̸͖̭̱̮̞̬͇̫̬̪͎̒̈́͑̒́͌͐̓͂̀́͑̓̚͜u̸̙̟̾̏s̶̛̛̩͙͚͍͕̼̺̺̱͗͌͌́̈̂́̉̉͜͠ǫ̶̢̜̬̳̬̦̥̭̫͚̱̐̄̒̌̓͜͠͝ͅn̵̩̘̖̤̪̖̭̜̬̜̎̅ͅ.̶̢̜̠̪̪͖̯͊̈́ ZALGO!

Kia atingo tiu rubaĵo estas!

PrimeMinisterK:The thing is, for me, I really don't care what the ending it. It doesn't matter to me at all. But it needs to be consistent. And furthermore, once something has been officially set in the language, then that should just be the way that it is. No reforms. No changes.

I think that we really, really should be sure to adhere to the original goal of the language being a regular language that is as easy to learn as possible. Once we start changing things to suit our whims or appease complainers, this cause is lost.

A sovereign state has a right to choose its name. In the name of mutual respect other states try to follow that suite. Note also that there are country names that are far older than their contemporary states. Since Esperanto aims to be internacia lingvo, a drastic deviation from those established names would be counterproductive (e.g. Zamenhof's later (toy-)idea to name countries after their capitals). Besides who could decide what "a consistent" naming system would be? So that all would agree to it.

Oh, all living languages evolve – if they do not, they will die. We need new words and expressions to express new things and phenomena. These might cause changes in the grammar. And Esperanto has changed. Let me list just three changes.

In the early years it was not so clear what preposition goes with what verb, so the "joker preposition" je was widely used. Nowadays the use of je is more limited.

Zamenhof left rather open when to use simple vs. complex verb forms, but thanks to Kazimierz Bein (Kabe) we now mostly use the simpler ones.

A great change that has gone undetected for the most part, concerns the perfect vs. imperfect aspect of verbs. We simply use less forms like "faradi" and "ekbezoni" than in the early years.

Do not take my word for the changes, take a look at early texts to see it with your own eyes.

And don’t get me started about the “devintus/povintus” faction.

Oh, we've been down this road before. I must get you started.

This is a problem that needs to be solved, if only for the peace of mind of English speakers. There is NO word or construction in Esperanto which means "should" the way English has it. And it's only a tiny exaggeration to say that English speakers only use that word every third sentence. Apparently other languages manage to get away with not having a word for "should", but that world is simply incomprehensible to many native English speakers.

Devintus, a word that manages to somehow combine inelegance, imperfection, and just outright awfulness into one clumsy word blob, STILL seems necessary to many of your typical native English speakers, because it's the only thing that even marginally maps to one of our favorite concepts - that of identifying the best course of action without implying an obligation to perform that action [1]. We really like that idea, and use it constantly. But nothing in Esperanto maps to that. We need a new root.

I propose "ŝud-", which Lernu!'s vortaro doesn't register as a root, although that's the extent of my research. I am going to claim that anyone who doesn't support this new root, by default, should be considered a supporter of devintus, and those people therefore should be ashamed.

OK, I'm joking. But seriously, we need a word for this. The word "should" is just too central to one of the major international languages to ignore in what should be THE international language. Esperanto needs something that covers this conceptual space. -us doesn't do it fully. Devintus doesn't either, but people try to bend it into that shape.

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[1] Not necessarily an official dictionary definition, and is probably incomplete, but generally is how it works.

Also, povintus is just as much of an abomination as devintus, but I don't think it comes up as much.

Oh, we've been down this road before. I must get you started.

You have been duly warned. I am thankful, though, because what good is a pet peeve, if you don’t rant about it frequently? So, here goes:

OK, I'm joking.

Close call. I was already setting up my rant keyboard and cracking my fingers.

Moving on. I can somehow accept “devus” for “should” considering the use of “modesta us-formo” or some elided conditional phrase:

I should go now. ≈ I ought to go now. ≈ It would be wise, if I went now.
Mi devus iri (,se me estus saĝa).

I personally would use something like “Mi iru nun”, but the “devus” doesn’t break anything important. The faeces however hit the climate control device with “should have”.

In Esperanto verbal forms can mark either absolute tense, relative tense or no tense at all.

Absolute tense:
-as: present or gnomic tense
-is: past tense
-os: future tense

Relative tense:
-ant,-at: concurrent
-int, -it: anterior
-ont, ot: posterior

No tense:
-us, -u: tenseless

Where does this tenselessness of the -us/-u forms come from? Let’s remember that LLZ spoke at least one Germanic (German, ¿Yiddish?), one Slavic (Polish, Russian) and one romance language (Latin). How do these language families express the irreal mood (irrealis) both for the present (irrealis praesentis) and for the past (irrealis perfecti)?

While English, German and Latin use distinct forms for the irrealis praesentis (namely the subjunctive imperfect) and for the irrealis perfecti (namely the subjunctive plusquamperfect), Polish and Russian use the same form for both (namely the resultive participle plus the perfect aorist of the verb “to be”, or what is left of it). E.g. the Russian phrase “он бы был богатым” means both “he would be rich” and “he would have been rich”. Apparently LLZ liked the simplicity of the slavic system and incorporated it into Esperanto. That’s why we don’t have any tense marking in the irrealis (us-forms). (The fact that we don’t have a past perfect (plusquamperfect) in Esperanto has probably a similar reason.)

But is this ambiguity a problem? It is none for Poles and Russians, so why should it be one for Esperantists? These tenseless us-forms get their tense from context; they have to latch onto something in their surroundings.

- Kial vi ne venis al mia festo hieraŭ?
= Ĉar mi ne havis monon por la buso…
- Se mi scius tion, mi pagus al vi Uber.

This can only mean “If I had known, I would have paid” and not “If I knew, I paid”. No ambiguity.

- Kial vi ne manĝas tion, kion mi kuiris?
= Ĉar, se mi manĝus tion, mi mortus.

This can only mean “If I ate, I would die” and not “If I had eaten, I would have died”, because the speaker obviously is alive.

We will find ambiguities only in constructed examples devoid of context, but never in a real discourse.

Enter the intus-enthusiasts: “This is an abomination! “I would die” and “I would have died” are two completely different concepts and thus we need two different verb forms for it!” Unfortunately, -intus doesn’t work the way they think it does.

If you had arrived at 9 o’clock sharp, I would have let you enter.
Correct: Se vi alvenus precize je la 9’a, mi permesus al vi eniri.
Brain-fucked: *Se vi alvenintus precize je la 9’a, mi permesintus al vi eniri.

Let’s dismantle this ugly love-child of ignorance and stubbornness:

Se vi estus alveninta precize je la 9’a. The “estus” is tenseless and needs to latch onto something, in this case onto “precize je la 9’a”. So the whole phrase is fixed to 9 o’clock sharp. Now the “alveninta” marks relative tense: it happened before our reference frame, i.e. some time before 9 o’clock. So it doesn’t mean “if you had arrived at 9 o’clock sharp” but “if you had already been there at 9” or “if you had arrived before 9”. This is how -int- works. “Hieraŭ je la 9’a li estis mortinta” means he died before 9 and at 9 he was already dead.

So, this is the basic problem: “se mi povintus/devintus/farintus/fikintus” is grammatically 100% valid, however, it does not mean what its zealots think it does.

English— It can’t be that “mi farus” means both “I would do” and “I would have done”. We need a new form!
Russian— It can’t be that “mi vizitis” means both “я навестил” and “я навещал”. We need a new form!
Spanish— It can’t be that “mi vizitis” means “visité”, “visitaba”, “he visitado”, “había visitado”, “hube visitado”, "estuve visitando", "estaba visitando", "he estado visitando", "había estado visitando" and "hube estado visitando". We need a whole string of new forms!

English— It can’t be that “dividi” means both “divide” and “share”. We need a new word!
German— It can’t be that “la samo” means both “dasselbe” and “das gleiche”. We need a new word!
Spanish— It can’t be that “esti” means both “ser” and “estar”. We need a new word!

LGTBQIA2S+— We need a new pronoun for pansexual, polyamorous, genderfluid, transhuman, non-binary individuals.
French and Italian— We need new pronouns for “en/ne” and “y/ci”.
Spanish— It can’t be that “vi” means “tú”, “vos”, “usted”, “vosotros”, “vosotras” and “ustedes”. We need a whole string of new pronouns!

Japanese— It can’t be that “unu” means “一人”, “一本”, “一個”, “一匹”, “一頭” and “一台”. We need new numerals!
Spanish— It can’t be that “mi farus” means both “haría” and “hiciera”. We need a new form!
Slovene— Dual, please?
Finnish— No niin! I’d like to order 28 new cases.
Mayan— And don’t forget ergative and absolutive. Also, change the alignment please.
Japanese— We need words for “あげる”, “くれる” and “もらう”. And honorific prefixes on the side.
Latin and Finnish— Please decline infinitives.
Portuguese— Personal infinitives, too, please.
German— And separate words for “Angst” and “Furcht”.
Italian— Geminate consonants would be sweet.
Mayan— And ejective and glottalised consonants, too.
Arabic— Three vowels is plenty.
Klingon— Heghlu’meH QaQ jajvam!

So, this is the basic problem: “se mi povintus/devintus/farintus/fikintus” is grammatically 100% valid, however, it does not mean what its zealots think it does.

I know! That's my point, though. It's being misused, and horribly so, but the reason it's being misused is because there's really nothing that takes the place of "should" in Esperanto, and we really want there to be. And the misuse is something which everyone seems to kind of know, but are ignoring anyway. Devintus is becoming (or maybe just is, by now) partly idiomatic. It's being assigned a meaning that it's parts don't mean. And make no mistake, I'm not excusing anything here. I don't use it. I don't want anyone to use it, except where it belongs. But I see it.

MY point is that it sure would be nice if we somehow came up with a way to express the English "should" better than we have now so devintus can go back to being used properly. Because "should" in English isn't some weird edge case thing that hardly anyone ever uses. It's super common.

That may not mean inventing a new root, though, or new grammatical rules. You brought up the word "saĝe", which actually suddenly struck me as potentially useful in such a construction (although I have not given that a LOT of thought). But that is leaning in the direction that "should" lies. Technically we should be able to fabricate a word or expression that is fully Esperanto. I just haven't see one yet (or invented one) that seems to do the trick. On the other hand, if "eldoni" can mean "publish", then I'm not necessarily against doing something mildly idiomatic.

Mi ŝudas pensi pri ĝi.

I should also point out to beginners that the argument...

On the other hand, if "eldoni" can mean "publish", then...

... can be used to justify nearly anything. Which means it's a strong conceptual spice that you probably shouldn't use too often in the dish that is Esperanto discussion. More than one or two mentions in a year in any forum is probably too much, and I've kind of used it up, here, so, sorry to anyone else that wanted to use it to justify some other questionable thing. You'll have to think of something else now.

But nothing in Esperanto maps to that. We need a new root.

Once upon a time, in land far, far away, there was an Proto-Indo-European root “*skel-” which meant something like “debt”, “owe” and “obligation”. From this root sprang the Proto-Germanic verb “*skulaną”, thence Proto-Western-Germanic “*skulan” and finally Old English “sċulan”. The German “sollen” and “schulden”, the Dutch “zullen”, the Skandinavian “skulle”, the Esperanto “ŝuldi”, the English "shall" and "shild" are all derived from this one ominous root.

The OE “sċulan” was inflected as follows:
“ic sċeal” = “I shall” (DE: “ich soll”)
“ic sċyle” = “I shall, but subjunctive” (DE: “ich solle”)
“ic sċolde” = “I should, both indicative and subjunctive” [1] (DE: “ich sollte”)

Sometime later the present tense “I shall” was used to form the (newly invented) future tense as in “I shall go”. The past tense of “I shall” is still “I should” as in “I told him, I should go tomorrow.” But the past subjunctive turned into the auxiliary verb “I should”, which litterally means “mi ŝuldus”.

This is why adding a new root to Esperanto for the concept of “should” doesn’t make any sense. Neither in English is “should” its own root, it is just an inflected form of “shall”.

What shall we do with the drunken sailor? = Kion ni faru kun ebria maristo? (although here we have "shall" instead of "should", I think it is the same concept of pondering and deliberation, weighing the options of how to help their stricken shipmate)
Should I stay or should I go? = Ĉu mi restu, ĉu mi iru?
Thou shalt not covet thy neighbour's oxen. = Ne avidu la oksojn de via najbaro. (The future tense here is just a word-by-word translation from Greek/Latin)
They should be ashamed. = Ili hontu.
It should me possible. = Supozeble tio fareblas.
I should take my leave now. = Pli bone mi foriros nun.
You shouldn't do that. = Estus pli saĝe ne fari tion.

- - - -
[1] Only strong verbs have distinct forms for the indicative and subjunctive of the past.