both charlotte and ga st are likely cusa candidates in my opinion once they get their programs going as both have clearly stateed a desire to go 1-a. ga st could also go in the sunbelt in the mean time, as the sunbelt is looking at having 11 members, as they could be a solid fit in either conference. charlotte would be an odd duck in the sunbelt and i don't really think they would leave the a10 for any conference but cusa or big east.
i do think that down the line once these east coast programs upgrade you will see a cusa split or a new conference formed, depending on what (if anything) the big east decides to do as right now the cusa is a big marriage of convenience and necessity.
We do know that the CUSA east schools have felt alienated from the west/Texas group. The problem has been the numbers and the future. in my mind, CUSA will never do anything until the Big East does. In other words, there are so many BE scenarios that could effect CUSA schools again: 1) Big Ten expands with a BE school = BE takes a CUSA school, 2) Big East splits and invites 2-4 CUSA schools, 3) MWC expands and adds 1 to 3 CUSA schools...
CUSA schools will be hesitant to make any big moves with upgrades on their table. Sunbelt on the other hand, those schools will jump at any upgrade that comes like CUSA.