FSRS is really cool. I'm trying to use it and a modified flashcard system to learn more abstract computer science and higher math. I hadn't considered it as a way of learning Chess - that's really interesting. I'm thinking about expanding my system to cover ear-training, birdsong recognition, a few other things like that.
My listening comprehension for Piano has always been lacking. A deck of piano sounds that map to actual notes (or even chords) might do wonders for it...
My current decks are as follows - I spend about an hour in total reviewing/learning them all, daily:
Are you finding the French decks helpful? I'm also trying to learn French (not using spaced repetition _per se_ but Pimsleur [which does use spaced repetition, really], InnerFrench, and reading [currently reading _Le Trône de fer_]).
