Matt,
Maybe this is too simple, but if a Chairman or Director is causing a problem, there should be a clearly defined procedure (maybe there already is) for board members to complain to iHub Management (ie you). On a case by case basis Management can decide whether to remove a Chairman or Director. In particularly bad cases (SEVU?), Management can appoint an Interim Chairman (like the iHub Sheriff), and arrange for election of a new Chairman once things settle down.
Hopefully with Phase II a Chairman or Director can ban a particular user from a Board. So your role would be limited to dealing with evil or inept Chairmen/Directors.
I think there is an issue of minority rights here. Posts should not be removed because someone disagrees with a Chairman. Even if a substantial majority of posters on a board agree with the Chairman.
Good luck!
Steve