If you think about it, if you have conference championship games, it’s really a 10-team playoff, adding in the two at-large teams, that makes it 12.
The SEC could also do something like this. Have the best Division winner automatically get into the Championship game. But have the other Division winner have to play the next best team in the conference to get to the Conference Championship Game. There are a bunch of things the conferences can do on their own to essentially create a bigger playoff.
That would work, too. I just think 4 is too small, 16 or more is too big. No. 16 is too far removed from the top teams. I like 8 or 12, or your system.