How exactly will picking a faction work in game? Will you spawn and have to choose a faction for your character like in Mount & Blade? Or when you make your character you choose a faction, and for every match you are that faction?
I personally prefer it where you get to choose your faction when you make your character. Reason being is because just like in PlanetSide 2 or any other game that does that you will root more for a specific faction and get more in the vibe of having a specific team. If you go Mount and Blade style then players won't care about what side they are on as much. It won't create as much of a tension between factions in game.