I'd love to see more communities that cover topics outside of the usual STEM / STEM-adjacent / typical redditor interests. I was on another reddit-alternative a few years ago called tildes and it was ... shockingly like a microcosm of reddit. Like, it's hard to describe how narrowly-focused, how stereotypically reddit, the userbase's interests are. STEM, anime, gaming.

The music, literature, humanities, environment, city life and so on communities are excellent starts in that direction. And, despite the fact I'll never read anything there, the sports community is equally valuable for the same reason.

That said, something for tabletop games would be cool, too. Preferably something not D&D/MtG because we all know they completely take over every space they touch (like my FLGS... RIP).