Here are the choices for the AAC as rules are currently written:
1) Add a 12th football school so that they can continue to play a conference championship game.
2) Stay at 11 and get rid of the conference championship game.
3) Stay at 11 and play a conference championship game, but the AAC needs to play a round robin or 10 conference games. (Non-starter, especially for Navy which also plays Army, Air Force, and Notre Dame each year.)
4) Ask the NCAA to pass a new rule that allows conferences with 11 teams to only have to play 9 conference games to be allowed to have a conference championship game. (Think the NCAA and other conferences are up for this?)
The best choices for the AAC to add are Army as a football only (not likely, especially how this would impact the date of Army/Navy), BYU as a football only (Best candidate and could happen), or Boise St. (unlikely, but you never know). I doubt there are any other decent candidates at this time, but a school could develop in the next 5 to 10 years like Old Dominion, James Madison, or Georgia St., but you are not taking them at this time.
So, as much as we may think otherwise, the AAC could be backed into the corner and keeping UConn football is the best option.