If the Pac-12 proceeds with just OK and OSU, and the SEC only adds Missouri or West Virginia, and the ACC stops where they are, then there is a viable conference opportunity for the leftovers of the Big East and the Big 12. The remaining Big East teams would formally leave to join the Big 12, add a few of the most attractive teams not in, and the Big East would continue in name as a non-football league, just as it was when it very first started, and how many of the schools have wanted it to be for a while. You'd have a league something like this:

Kansas State
Iowa State
Missouri/West Virginia (whichever one is not SEC #14)
South Florida
with the potential addition of BYU, Houston, ECU, UCF, and maybe Boise State, or possibly Memphis or SMU, to give this league 14 themselves, and likely retaining AQ status.

However, if Texas and Texas Tech go to the Pac as well, and the ACC adds two more, this would likely kill the viability of the above scenario.