This isn't chess or go, where you either win or you don't. Chopin composed for a reason, and it wasn't just an excuse to throw a lot of notes at the page.
It might be possible for AI to work at that level someday, but it's not just a technical problem, and you won't be able to solve it by throwing a corpus of compositions at it.
Aside from that, this still sounds like aimless noodling. It's far more polished noodling with some awareness of genre cliches, but it's still essentially aimless - and so meaningless.