Reply count -1 would be nice, traditional forums don't consider the OP as a reply, so when I see 2 replies I expect two replies in addition to OP. And in addition to that, a last reply: name type feature would be nice, sometimes I refresh and can't recall if I read the most recent reply based only on timestamp + reply count, so seeing who replied last is also useful and a traditional forum feature.
In addition (and another.. often traditional forum feature), an archived section would be nice. Currently it seems some things are getting deleted - that guy getting roasted about the backbone, the post about the chat being closed down - to erase these from history seems a little against the ethos a lot of us probably share, so having some form of historical archive for threads that were closed would be nice. I don't like data disappearing without a reference - and it's not about the data itself, but just knowing if something was removed or not - Matrix still won't show the content (which would also be fine to not show here if chosen), but to at least see a thread was archived/closed like how Matrix shows a message is deleted, that would be nice to preserve the history.