There is no perfect way to do this. However, I think at least an 8 team playoff is doable. First in are the 5 power conference champs. Then based on some type of criteria that can be determined, 3 at large teams. Then of course it gets settled which teams get to play each other. The real issue is the total number of games that will have been played. Right now with conference championships, it's 13 or 14 games. Now your asking an additional 2 or 3 games for these schools. It's like an NFL season while still going to school full time. Again this format will have its downside but you at least get the top teams to face off and can achieve the goal of naming a true national champion.