You have to keep in mind that whilst they may act Human, the AI are still Nomads. Think of them as the Eldar from warhammer 40k. They'll trick you, make you do their bidding and sometimes even act as if they trust you and need you, then they spring the trap. So, I don't think alliances will be very likely. Also because of the fact that most trappers (the main force) act like members from different factions. That'd be a cluster screwup.