My personal opinion is that trying to crown a NC in football is a losing game. The only way to figure out who's truly the best team is to have a playoff system that features a series of matchups between each pairing of teams. Otherwise the "any given saturday" issue crops up and a lessor team gets hot on a given day and upsets a much better team. Unfortunately, a series just isn't feasible with football.
Everyone wanted a playoff...now we have one and the system is still flawed. Throw in more teams people say. Well, the more teams you put in the playoff, the less the regular season matters and the more it becomes a tournament championship, not a season championship (think how people view the B10 tourney championship in BB vs the "regular season championship").
People are chasing the ultimate answer for a game that doesn't really support it.
The real answer, for those who cannot live without crowning a "true national champion" (whatever that is) is 4 super conferences with two divisions each. Round robin play limited to the division, followed by a conference championship game between divisions (the quarter final), then the four champions are in a 4 team playoff. This system is still subject to the "any given Saturday" issue, but at least it's determined solely on the field with zero subjectivity.
Me? I'd go back to the 80's with normal sized conferences, bowls that were meaningful and some some fun water cooler debates over who was best. That debate will still occur with any other system. After all, look at this year...of tOSU wins it all, everyone will say "but PSU beat them".
As it is now, why not just give every team a bowl. People argue that the proliferation of bowls to the point of teams with losing seasons getting in a bowl is OK because "it's more football". It is more football, but if quantity over quality is OK, why not send every team to a bowl? At some point you either have standards or you don't.