Ah, this is a fun and wholesome idea! I hope nobody takes offense that I don't list 10 favorites here; these are just the ones that came immediately to mind. (Listed in no particular order.)
Everything by @Jared Steven Destro is meticulously crafted. I particularly enjoy his esoteric piano works, but this orchestral piece is so sonorous and textured. Beautiful!
@gmm is, of course, masterful at thematic development and orchestration; I would be remiss if his Adagio didn't make my favorites list!
This up-and-coming teenager, @jejrekmek, put me on my bum recently with his stirring piano piece/performance. And speaking of new members...
This recently-posted short waltz by @Greentealatte93 brings tears to my eyes every time I listen to it. It's so poignant and emotive!
And, of course, @PeterthePapercomPoser, king of variations! I love the adventurous harmonies and rhythms of this particular piece.
To round off the list, another bit of chamber music by ever-clever @Quinn! I always love the "dialogue" presented by his music, and this piece especially.
There are probably loads of other wonderful pieces I've missed... looking forward to everyone else's playlists!