Oh geez that’s tricky… My first instinct is to say Towa Tei’s Sunny, the entire album. But the thing is, half of what I love about it is the nostalgia about how much I loved it the first time, and where I was when I listened to it. So maybe it’d be better to pick something you might’ve liked better under other circumstances? In that case… Hmmm… I’d say the audio drama Spines.
Mirlo.space is working on federation too. I think they’re not as far along in that regard, but further along in terms of being a bandcamp replacement? Last I heard, anyway. I buy stuff from there, payment works.