Some redundancy in a language isn't a bad thing, as others have commented.

Occasionally in long sentences with both singular and plural items the pluralisation of the adjective can make it clear that the description applies just to the plural item, so making the meaning clearer.

But taking your complaint to the extreme one would also drop agreement of case with an object so instead of 'Ĉu vi vidas tiun belan longkruran virinon' you would put in the accusative only one of the words of the object - but would this be the first one (ie tiun) or the last one (ie virinon).

Yes, I realised that after I posted - but then German does have three different adjective declensions depending on whether it is used without any article, a 'der' type word or an 'ein' type word, so it is much more complicated than English or Esperanto!

As an anglophone adjective agreement is one of the stumbling blocks for any language learning but it's soon second nature and the more I use any particular language the more natural it seems.

darkweasel:

mjdh1957:Actually, the English language is the unusual one, in that it doesn't have agreement in case and number between adjectives and nouns. Most European languages such as French, German, Italian and Spanish do.

No, German doesn't - at least not in the sentence Kalantir is asking about.

German does have adjective-noun agreement when the adjective stands before its noun: ein großes Kind (one big child), zwei große Kinder (two big children). However, if you use a copula to link adjective and noun, there is no agreement: mein Kind ist groß (my child is big), meine Kinder sind groß (my children are big).