Screw it, go to a 16 team playoff like the FCS does succesfully.
All 10 FBS conference champs get an auto bid, plus 6 at large. Win your conference, you're in. Scheduling a tough OOC game helps you for an at large spot. Seed where the first two rounds are played at the higher seeded home stadium. Final four then go to the current CFP system of bowl tie-ins.
If you're worried about losing to a MAC, AAC, or even a .500 team in the first round of the playoffs, then you don't deserve to be a champion. Hell, UVA was the first 1 seed to lose to a 16, and we can all agree that's great for fan interest.
This scenario has been discussed many times over for a decade plus, but I still see it as the only scenario that every FBS team has a chance, while allowing for tough scheduling in at large spots. With as much subjectivity in rankings, this will settle it on the field. I mean, the Giants are still considered the champs over the Patriots.
Don't give me the "every game matters", BS, because you still have a chance at an at-large with a loss. Defined goal of win your conference/what's on your schedule and you're in the playoffs. You may have to win 4 more games to be crowned NC, but if you do, you're winning 4 straight against the best of the best. Who can really say that they didn't deserve the NC after that?
Pipe dream, I know. However, you did say if I was the Czar.