Dota 2 takes around 5 minutes to find a match and CSGO around 2. And the difference between those games and TF2 is that you all fill the same roll among getting into the game, unlike tf2 where having people willing to play medic / demo is always essential.
I think launching with anything more than one mode would slaughter wait times. People aren't willing to wait in a 30 minute queue for a medic/heavy/demo to show up. It just isn't going to happen.