When you stop and think about it, rankings are pretty stupid to start with. The top 25 is a list of opinions of how good some teams are. There is no objective criteria to determine what team is ranked where. The NFL doesn't have any sort of ridiculous rankings. The team records determine where they stand.
If college football really wants to be the NFL JV they need to follow the NFL model in determining who the champion is. Divide the country into four regions, Southeast, Northeast and half the Midwest, Northwest and the other half of the Midwest and Southwest. Put two 10 team "conferences" in each region and let each of those conferences determine a champion by playing a 9 game conference schedule. Send the 8 conference champions to a three round playoff to determine a national champion. There would be no need for any sort of rankings.