Just in case the NEC might get raided by nearby regional D-I conferences, would it be wise or not for them to add upcoming successful members from D-II conferences like the NE-10, the CACC and the former NYCAC-turned ECC? Plus, the possible addition of NJIT.
It couldn't hurt for the NEC to find a school from the D-II NE-10 conference to upgrade and join.
Bentley University would probably be the best option: They are near Boston (specifically Waltham), but have about 5,500 students, sponsor football and have placed in the top 3 in the conference Presidents' Cup each year since 1986, with 6 championships.
Stonehill College is also a good option: They are in Massachusetts but close to Bryant, have about 2,400 students, sponsor football and have placed in the top 3 in the conference Presidents' Cup each year since 2005, with championships in 2010, 2011 and 2012.
There are quite a few decent options, and Bryant joined from that conference and could be doing much worse. Bryant is overall better than NJIT since they've upgraded.