Teams will want to keep rivalry games. The first 6 games establish a seeding for the initial 128 team bracket. Beyond that you would have a middle and lower bracket to begin filling with one and two loss teams respectively. Winner of top bracket plays winner of the champions in the lower brackets. There are challenges. Worst team might only play 9 games. There could be games added for eliminated teams. Who gets home games? Could get very skewed. One team in the championship will have zero losses. Is it win or go home at that point? Football isn't known for a series. It would be a complicated mess since it isn't a strict single elimination bracket.