SEC teams normally don't have to play more than 1 quality OOC game a year because their league schedule usually supplies enough opponents to make the schedule tough. This year the SEC happened to be not as deep as in prior years which hurt Alabama along with FSU completely imploding after losing Deandre Francois. As long as it is allowed, SEC teams will buy 1-2 wins a year.
As for the top 4, I think whoever the ACC and SEC champions are will get in no matter what so there's 2 spots taken. That leaves 2 spots for Wisconsin, Oklahoma, Alabama, the ACC/SEC title game losing teams, and Ohio State. I don't think any other teams have a shot. If Wisconsin and Oklahoma win, they clearly get the 2 other spots. If they don't win, then the debate will begin.