Communities generally spawn on whatever general purpose instance, and I’m fine with it because the only other option is usually nothing at all. Maintaining an instance takes hard work and money.
Sometimes there is enough will to spawn a specific instance. For example, rimmers have their own mbin instance. That’s the exception, though.
The only encouraging thing I can say here is Be the change you wish to see. If you want an instance to exist, run it yourself!
I guess just try gnome and then mint cinnamon if that doesn’t work out. Both are simple, but different kinds of simple.
Edit: yea I didn’t read the post perfectly the first time. Might still be a good idea, at least I’d try gnome first.