There is no real good answer with playoffs etc.. there will always be someone bitching about it. Say you have a playoff where the top 8 teams get in, whoever is left out at number 9 will be bitching about their lost opportunity.
In your 1vs 4, 2 vs 3 playoff scenario above, why reward a team like Texas by giving them an extra game to try to beat Oklahoma.. that is what makes college football so great, you lose once during the season and it effects your rankings.. Every game is crucial. Every game counts.
Leave it like it is, tweak the voting because not every coach can watch each team during the season so they have no clue except what they hear on ESPN. That is the real problem here. REalize that Lee Corso and his idiotic mind has more influence on which teams are voted where just by what he says on TV. Now that sucks.
Leave the system how it is, and tell everyone to quit bitching. Play the toughest schedule in the country and win every game and you get to be champion. Lose a game and all bets are off.