I think it'd be interesting if slots could be used for anything. That way, if you wanted like, just your core 5-10 units and a bunch of support powers, you could, or if you wanted no support powers but 20 units, you could do that as well. Still, I think this looks a lot more structured than End of Nations. It looks a lot easier to tell a player's combat role in Victory.
Great idea Brandon! We can't wait to get the community in the game to give you a better look at exactly how it's designed for this :).