I feel like you're right about this one.
Using these as some sort of "flair" would be best. While there's always a place for more specific fandom communities (ex: Zelda, Pikmin, Mario Kart, etc) the other communities can feed nicely under the umbrella of just "Nintendo"
First comment from it, and I’m totally digging it over Mlem. Something about it feels more familiar to me already as a longtime RIF and Narwhal user!