4hundred: It is definitely going to help new players get into the game, as it will make it easier to just press a button and go, no need to worry about how many are in the room already. So long as the maplist is good, the competitive people should be fine with it. If they want to play series against specific opponents, those rooms are available as well, so that's perfectly possible.
I also think a spectator queue is a good idea. However, because the infrastructure currently doesn't hide who is in what room, it's hard to support the idea of only having spectating of some random game (within a type, perhaps) as opposed to choosing a game to spectate based on the players.