This is something that made me stop using Mastodon, too many instances with bad method of connecting them. I'd much prefer that instances aren't seen to the user (I wouldn't mind somewhere with the text "this community is hosted by X on server Y"). But seeing @username@instance is weird and many Reddit refugees won't have any idea what does it mean. I mean, the concept of federated network is complex already.

I've also encountered a lot of bugs in my short time of use which I'd like to see fixed, but I'm not sure where can I report them, or to see if they are reported already.