So with matchmaking on the way, I think it's a good time to start talking about gamemodes and the flaws surrounding them. Right now almost every mode is seriously broken in some way. Let's make a list of the problems. I'll split them into two categories: flaws/bugs and missing features. Note that this isn't really the place to dream up new modes, its more focused on fixing the ones we currently have.
Joining players are automatically added to the game, causing afk joins while they load the map.
Disconnecting players are lagged out instead of removing them, causing afks and hitbox/model disconnect
no autoremove for afks, again causing afk players..
Gonna include workshop sorting issues here, because finding good maps is pretty important to the pub ffa experience
No teamsize or lock team options. 2v2 does not exist in the game, despite having a 2v2 mapping contest..
Team info widgets in default hud is really important to tdm
Arena mutator removes flags from map
team info by default again would be really important here
scoring for non-cap events
Weapon movement is terrible with ping
spectating deletes score
no option to hide other players
ghosts to race against, of fastest player or personal best
spectators count towards votes
Occasionally the order of the people in queue is mixed up. (Xytaglyph's post for details)
missing items at start is still a thing
changing name moves up in queue
Forfeit option while preserving stats
All things considered, duel is the most complete mode I think. Would love to hear some issues others have with it.