Face it, the big conferences make the game what it is. Why should they reward their underachievers with a shot at another conference's top team when THEY haven't earned it on the field?
With a goofy 16 team playoff, you'd get an NFL look-a-like. A 9-1 team with a playoff spot locked up would rest their good players in the last game thereby screwing the fans who buy the tickets. Not gonna happen.