I was thinking about a 16 team CFP that would all conferences (P5+G5).
Their is no way the P5 ever allows a traditional bracket (too many games for the top end teams, injury risks, etc.)
Every conference Champ gets an auto bid. The Top 4 get byes to the quarterfinals. The 5th (per CFP ranking) gets thrown in with the wildcard teams (that are the next highest rated teams per the CFP rankings, regardless of conference).
The G5 conference champs get an autobid as well, but unless they are higher rated than a wildcard team, the autobid lands them in the 11-16 mini-bracket (think play-in game). The 11-16 play-in bracket are the G5 champs + the worst wildcard team. The winner of this mini-bracket gets to play the number 1 seed. I made a graphic on how this would play out by week one's CFP rankings.
It isn't "fair" to the G5, but at least we can say that we control out own destiny to play for the title each year. Also, this would generate insane amounts of TV revenue. Play Each game until the Quarterfinals at the better seed's home site, or use some of the lesser bowl games as sites. Quarterfinals and up can replace the big boy bowls.
This will probably never happen, but I think it would be fun to see and it protects the P5 (which is the only way they would agree to anything like this).