I agree with most of VUGrad1314's post but I think some of the dynamics are changing with the Group of Five football conferences. It really feels like the Sun Belt has stabilized and found their footing as a conference with small but passionate fan bases. I think the AAC is going to need to find their footing after the recent upheaval of schools, before Sun Belt teams would want to join the conference (I am aware that a future AAC team just made the Final Four). SMU to the Pac-12 seems to have a lot of traction and Memphis will leave the conference at any chance they can get. Do schools want to leave the Sun Belt for the AAC without those 2? I'm not sure they do.
That being said, money talks and if the TV contracts are still substantially higher for the AAC than the Sun Belt than this is moot point.