This feature seems really cool!
Any reason to have a button for "show me more" when there's also an upvote button? But good idea to separate "show me less" vs downvote
I guess another thing you could do is sort a list of communities by how many upvotes you've given to them, then you can easily subscribe to communities you didn't know you liked
That would make community names a bit longer so they'd be more annoying to type and share?