Accountability and transparency in moderation. You aren't even made aware when you're banned from a place, you have to go out of your way to see and even then you have zero recourse in changing the decision if it was made in error. It's even worse when you get banned from your instance because it's just suddenly you can't log in and you don't even know why. You can't even transfer to a new instance. Pretty shit for something that can be done on the whim of a single person.

Somewhat related, as Lemmy continues to balkanize between pro-fascist instances (such as lemmy world, sh.ithole, and beehaw) and those explicitly against it (lemmy ml, lemmygrad, hexbear) the only way for users to opt out of interacting with users from those instances is to get yourself banned from the instance itself. I don't mince words and have a zero-tolerance policy for injustice so it's not hard for a person like me to catch those bans, but that's hardly ideal for the federation as a whole to have to rely on something they can't control in order to have a tolerable experience not constantly marred by some of the shittiest harassing assholes the federation has to offer.

EDIT: Maybe outright comment blocking on instances is a bit much, but absolutely auto-hide should be a thing.