Atma yesterday thought that the quick-replay option (Atma hacked once to steady appear), normaly closed left lower corner, if making it fix and open, at least for mobils, maybe add simple button for uploads, would make use easy and common appearing.
Making it broad as the screen, remove infotext, should be no problem, as well as to set up as open by default.
For embedding attachments there are mods. For adio, video, they are already used. Just the recorder was never brought tnto right attention and Atma isn't able to implement a voice-recorder. Then, using simple symbols, lesser text, soon the forum gets more "chat" like, althought autorenew of topics when new post is something supported by smf >2.1