Well I'm not sure about other maps, but I don't think that the rebels should get artillery on Hoth. Since there weren't really any specific arty units in the movies, maybe they should only give a team artillery if there is evidence that the team had orbital support in the movies. I'm not sure how that would affect gameplay tho, it might frustrate the rebel commanders. Maybe they could get more bonus points if they win than Imperial commanders. i.e. rebel commander gets 2.5x bonus for a win while Imp commander gets 2x bonus for a win.