Wow! This is just beautiful! It must have been quite a lot of work. Only I must say, the declination of "Ainu" in plural looks quite... strange. But that's normal, of course, adopting words from other languages leads to transform them, and especially Latin had its share of it... but plural "Ainua" must've sounded terrible in Elves' ears
Anyway... great work!
(it occured to me that I might attempt to rewrite Ainulindalė in ancient greek, but who'd bother to read it?
)