The current solution to put you on a separate chat channel doesn't really work.
1) If you quit/surrender, there is nobody in the room... for a few hours.
2) If the game really is over, they are probably glossing over the graphs, so there won't be anyone for a few minutes.
3) If you were not the first one to leave the game, the previous guy probably got bored after 3s of sitting in the empty channel and is already in the Lobby1 room... or maybe the next game.
4) Lobby1 is too quiet anyway. A few guys discussing their game wouldn't hurt the athmosphere at all! At least you know these guys are not AFK and you might be able to pick up some clue about what kind of games they like.