There are no 3 AP skills -- the most likely reason? It would be clunky with the 4 AP base system. Now, if you're talking about specifically about the 1 AP Warfare skills -- I could see some change in that. But in that case let's not forget about the 1 AP Teleport, Hail Strike, Winter Blast, and whatever else exists.
Actually, Fireball costs 3 AP. Just sayin.'
