Problem expanding the playoffs is answering the question "How many teams fans will be able to travel to more games?"
Four is enough. This is College not the NFL where players make their livelihood's. It is not wise in my opinion to extend the season over 2 games.
The FCS is doing it now and attendance suffers as well. Four is plenty in FBS playoffs. The well being of the players is also a consideration.
Making a 16 field playoff where the first round is conference championships would only add one playoff week for 8 teams, to the season. The benefits of this model include:
1:) No committee, holy rankings, corruption and bias.
2:) Teams would be seated by record and head to head.
3:) This model is similar to all other sports.
4:) One playoff champion.
5:) Increased importance to every game
6:) Keep the bowl game TV money
7:) More high quality football!
8:) No more Kirk Herbstreit telling me his opinion is truth.
Pointless bowl games struggle for attendance. Playoff games are SOLD OUT!