The 81mm mortar is over performing. It also mess with faction design.
USF went from having weaker support weapon to having the best mortar in the game coming earlier than any other mortar.
81mm has more range less scatter and better vet bonuses then other mortar and it only cost 20MP more. The mortar of should either be nerfed or delayed or other aspects of USF game should be nerfed like the far DPS of riflemen, the smoke grenades the forward retreat point and the movable healing reinforcing points.