Embed Notice

This one feels like a really obvious thing missing from BirdSite, but is a combination of two features:
1. You can "lock" your account to put follow requests in a review queue.
2. You can mark a post as Public, Unlisted, Followers Only, or Mentioned Only.
As a consequence, you have an option between "fully open" and "fully closed". A locked account can still make Public posts, so you're not damning yourself to eternal solitude just to get some privacy.