To be honest, faction backgrounds are probably one of least developed aspects of the game at this point. That doesn't mean there's nothing at all though, we're far from that. We defined the basis of all factions, and some of them are more advanced than others, but all in all, faction NPCs currently fit a role that is usually more practical than authentic. Only the Brahminboys are advanced to the point where almost all of their members have their own story to tell you about.
The main reason for such a situation is probably that we have no dedicated writer in our team. Most dialogues have been written by John, which is also our lead designer (if you can believe that is even possible!). For now, we've been focusing to make sure every character has something to tell you, that you can interact with them, getting some opportunities or information from them.
Later on, we'll extend faction backgrounds to the point where playing in one will concretely feel different than the others. That feeling will come from those backgrounds and content related to them, like the equipment available at merchants, particular assignments, also dedicated locations related to headquarters, and of course the main storyline. But for now, this is not our main priority, and this doesn't prevent the game to be played fully.
For now, we also want to leave some space to the players to discover the factions and come up with their own stories for them. We hope some of you will be interested to contribute and assist us in this aspect.
One last thing I'd like to add is that you shouldn't expect factions to resemble those from Fallout episodes in term of background 'focus'. Imho in Fallout games, if factions were deeply designed, often having opponents outside but also inside their ranks, they also had a quite defined personality, with strong character traits and clear centers of interest. In AoP, we want factions to be societies, of a size that includes all the strongest personalities, but also their opposites, to the point where you could not even determine if a faction is blacker than white anymore. Corrupted selfish bastards and honest enthusiastic altruists can be found in the same faction. It's a bit like if you consider New Reno as a whole, instead of one of its families alone. Our general goal is to provide players with the basic traits that define the very nature of the faction, and then leave enough space to come up with any kind of background they'd wish to develop around the vast circle of possibilities.