I was looking at making a 64 player game type become a major selling point for the next game to detract. It would also take away from developers focusing on smaller game types. I just believe that the quality of the smaller playlist would be jeopardized. Thanks for pointing that out I should of emphasized my point more clearly.
I personally think that the small team CQC formula is great. In fact its because 343 didn't have a bigger playlist/gametype to focus on that they ended up added different features which a lot of people didn't like.
Bigger gametypes won't harm smaller gametypes. At the minute, the population of halo 4 shows both sides are harmed, making big team bigger can't hurt small team any more can it?
EDIT: I had a similar argument with someone about campaign matchmaking.
They said: It would decrease population of multiplayer matchmaking
WRONG. If people are going to play campaign, they're going to play campaign, whether its with a friend, on their own or with strangers. In fact being able to play the campaign more freely may even encourage campaign players to expand on their gamemodes.