SMU to the Mountain West seems obvious. Maybe Memphis or Tulsa to go along with them? UTEP and New Mexico State belong in the Mountain West but I don’t see that happening.
The new WAC is going to go FBS as a group. That's where UTEP and New Mexico State end up. New Mexico will block NMSU getting into the Mountain West.
I think you're right about Tulsa and Memphis to the Mountain West, especially if Gonzaga ends up there for basketball.
The AAC is just going to end up as CUSA with a different name and worse geography.