The ECHL's PR guy, Joe Babik, speculated on the Everblades broadcast that he thinks the ECHL could get to 32 teams over the next 4-5 years.
There's a lot more versatility in where you can put an ECHL team, but every division in the ECHL right now is 7 teams, except for the Mountain Division, which is 8 teams.
The northeast could honestly use another team. There's enough NHL and AHL teams to justify it. NYR are affiliated with Bloomington, IL. Ottawa are affiliated with Allen, TX.
Albany, Binghamton, and Manchester, NH could work. There's been rumors of Ontario getting a team, but it's a tough market for anyone not named the Leafs.