1) there are no good and bad guys in OP2 (both sides are struggling to survive, and if it weren't for their opposing philosophical ideals, they would have just gotten together, built 1 space vessel that could hold more people)
2) there is no imbalance in the colonies. Eden gets the heavy guns, plym gets the ability to steal them (and with enough emp tigers, it's very easy)
3) in multi, plym owns eden almost every time (rushes on small maps, supers on large maps)