Things Mastodon probably needs to grow:
1. a much better "migrate from Twitter" tool (the current tool is a bit slow)
2. better ways to discover people to follow (by interests and language). Currently, the main way I'm finding people is looking through the timelines of people I know. This seems like a recipe for filter bubbles.
3. account migration (I know, it's being worked on!)
Server run by the main developers of the project It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!