I got your answer right now.
a 16 team tournament.
all 11 conference winners get in automatically.
You put it in 4-4 team regions, trying to keep the teams within their certain region (North, WEst, South, East)
You determine, via the BCS formula, the 5 at-large bids. The qualifiers are that they must be within the top 16 of the BCS and cannot have more than 3 losses in a 12 game season (sometimes in college there are 14 game seasons).
And another thing, you don't allow any polls or rankings to come out until week 5.
Does Notre Dame have to be in a Conference? How are tie breakers settled? What if, let's say Ohio State is #15 at 9-2 and Maryland is 9-2, who goes? How do you come up with an objective system of ranking 117 teams, with a 12 game scheduled?
You are going to have to start the week before Labor day, no breaks, have all conference title games by Thanksgiving.
Then you have to expect teams and fans to be willing to spend bigs bucks on a moments notice.