The problem is that there is a card called Mercenary Loyalty that reduces its price, i think that free infinite mercenaries is very OP. I would suggest that the “Wallenstein’s Contracts” upgrade, in addition to its current benefits, reduces the amount of population occupied by mersenaries by -1 and increases the number of mersenaries you receive with each shipment of mersenaries infinites +1 of each type. In addition, the mersenarios in the tavern train faster. Also that they return the previous price that was 4000.