I think the concept sounds really fun, but I just feel the source engine is going to limit the game a lot and the 6v6 is really weak. I think 24-32 players is perfect. Not enough people you are being fired on all teh time, but enough targets to cause distractions and get some good flanks in.
But at the same time, I (and probably quite a lot of competitive players, not that I am one) think that 24-32 people is a complete waste of time, because it gets to the point where your results matter too much because of the quality of randoms you get on your team. I think that once you get above 8-on-8 or so, it's too hard to make a big difference in the game. It's why I would ideally see this stay 6-on-6, while removing the A.I. cannon fodder garbage.