Might have to go with five conferences of 16 (add ACC to the four discussed above). That would allow enough regional flexibility for BSU, BYU, maybe San Diego State and TTech to join the Pac. Eight-team playoff with the five champs and three at-larges. Bye-Bye Big East -- for football at least.
The 5 conference route wouldn't be too bad, but I would be more inclined to see for just 14-team conferences. Makes things a little more managable, is a bit larger than four 16-team conferences, but not too large to where you're scrapping the barrel to find those last few teams.