I do think Villanova will move up to FBS, and eventually join Big East Football
... and, of course, there is always Notre Dame to consider
barring talk of those two, I agree that Central Florida and Memphis make the most sense, and you could throw in East Carolina, Southern Miss, UAB, etc.
What about a disgruntled PSU, mad that the Big Ten decided to move west w/ Nebby rather than looking at Maryland or Rutgers? If PSU and ND decided to join the Big East, that would give the conference a huge population base, and two of the biggest name brands. Plus, it would realign PSU with their "natural rivals" ... Pitt, WVU, Syracuse.