My personal opinion is that there are the four main houses and now Gallia. Just because they are your enemy doesn't mean they get any smaller, in fact they've got roughly double the population of any other house because Igiss.
The Maltese Nation and Corsair Empire are the closest to them, but I wouldn't say they are actually at that level.
The Colonials do not claim to be a house, nor are they even large enough to be considered as such (just over 6 million people at the moment) although they are probably the most populous non-house group. Again, you don't get us "back into the Alliance" because we were never a part of it to begin with.
They, the Coalition (I think there are something like 2 million people eating rocks in O-52), the Council (not sure of numbers or declaration of being a Nation - likely intended to simply be rebels within the Gallic population) are the bigger groups who could be actual nations. Smaller groups who claim to be as such would be the Natio Octavarium, Molly Republic and someone in the Hessians needs to come up with a name for their little bit of space now they have taken half of Dresden to go with half of O-5 and -11.
