Don't get me wrong, I support a playoff system; and I actually like your idea to a certain degree, just the numbers as you presented them would never work.
Personally, my ideal for college football would be even more crazy and unlikely: go to four mega-conferences of 20 teams each and dump the bottom-feeders from the MAC, WAC, Sunbelt, etc. Each conference would be two divisions of 10 teams and you play everyone in your division (9 games). Plus, you get 3 games out of division, but you can only schedule other mega-conference schools--no bottom-feeders. This system would pretty much guarantee a school at least 5 home games a year, and it could be as high as 7 or 8.
You have your conference championships and the four winners go into a playoff. All other teams at .500 go to bowl games as in the current system, but again, without the bottom-feeders. Yes, to win the championship, you would have to play 15 games, but that would only be 2 schools. The overwhelming majority of programs would still only play 12-13 games. Oh, and did I mention, I don't want any bottom-feeders!