America East is down to 8 and desperately needs 2 schools. The MAAC is down to 10, but their commissioner has stated he would like to be at 12. The NEC is at 10 and is home to the likely expansion candidates for both leagues.
The last additions to the AE have been - NJIT (ASUN); UMass-Lowell (D-II), UMBC (NEC) and the SUNY-3 Albany, Binghamton, and Stony Brook (D-II). The last additions to the MAAC have been - Quinnipiac (NEC), Monmouth (NEC), Rider (NEC), and Marist (NEC). Both the AE and MAAC have lost teams to the CAA and Patriot.
Here's what I see as the top-3 candidates for each league:
America East - Central Connecticut, Bryant, Merrimack
Metro Atlantic - Wagner, Mt. St. Mary's, Sacred Heart
Problem for the NEC is if they lose a total of 4 teams to 2 conferences, they will be down to just 6 members. The only rumored candidate for the NEC is D-II New Haven, bring a total of just 7 teams.
One caveat, is the NEC sponsors FCS football with an AQ. 5 of those 6 schools ripe for expansion to other league play football and would have to find a new conference for football. Both the MAAC and AE do not sponsor FCS football. The NEC has has not let former members (Monmouth and Robert Morris) keep football as an affiliate once they left the league for all sports.
I think CCSU would be a natural and logical fit for America East, but finding a home for football is a challenge right now. Same for Bryant, Wagner, etc.
The MEAC has strong cultural bonds, and unless Howard decides to leave, they may hold on for a while. If the Bison bolt for anywhere (CAA in later years), the NEC and Big South could divide up the remaining MEAC schools.