All these suggestions of 6 or 8 teams fail to solve the eye-test bias. A true championship playoff should be determined on the field of play rather than in an ESPN studio or in the luxury suite of a hotel.
Right now there are 10 conferences playing FBS football. All of them get 85 scholarships. All of them have the same # of coaches. Then all of them should have access to the national championship.
If the SEC is so better than the Sun Belt, it should be seen on the field. The only time I would allow a committee to be involved would be in seeding the 10-team field of conference champions -- and ONLY conference champions. If an 8-4 team upsets a 12-0 team in the CCG, so be it. The playoff is made of champions, not coulda-shoulda-wouldas.
The committee's role would be to seed the 10 league champions, with #7 playing #10 and #8 vs #9 to get into the final rounds of 8. Then it would be 1 vs 8, 2 vs 7, 3 vs 6, and 4 vs 5. No at large teams, no media darlings, do Herbstreit beauty winners. Winners and only winners of actual championships enter the playoffs.
Let the beauty queens play in the Alamo Bowl ... I'll watch them.