I think it's pretty clear through two rounds of realignment that the AAC is going after markets and endowments and App State doesn't fit this profile at all. Texas State, Georgia State, Old Dominion, Middle Tennessee, and Buffalo do.
Of course, anything is possible and the AAC could do a 180 and start going after more established programs with a history of successful athletics located in small markets but outside of ECU and the service academies, it's never gone this direction in its entire (albeit short) history.
And considering new programs only get partial media revenue and half the conference is desperately trying to get out, I'm not sure why anyone would want to be a part of that mess in the making.