While I agree that a playoff would have to include conference champions, I would disagree about the at-large bids. 11 conference champions only, highest-rated get first-round byes.
That way you MUST win your conference to play for the NC.
I put the at-large teams in there to keep the BCS pimps happy. But the only true playoff system is one that takes ALL 11 conference champs. By the way, do you know what the true meaning of the acronym BCS is? Big Crock of S@#t!