I like the idea of Mercenary Camp for Mercenaries, but here are the stats I am considering: Requires Currency tech; +3 ; +2 ; +1 with Alcohol. The +3 gold will help you maintain a garrison, but then you'll need to spend money to maintain a field force. The unhappiness can be moderated by alcohol, but not totally removed. I don't want to mess with health here. Happiness is more valuable than health at this point in the game.