For me flair is probably the most important. I follow a lot of organized sports and being able to quickly identify which team someone supports helps the conversation move along without having to write “as a fan of…” in every single comment. And this isn’t a like talking shit, sports guy thing. It’s genuinely extremely useful for broadening the depth of the conversation.
Also not having to scroll to find the reply box. Super annoying. Super easy fix.
That being said I’m all in on kbin. Deleted Reddit. Not going back.
Point 1 is paramount. 5 is important also from a tech standpoint. The rest are very good points.