Mortars would be a great addition to the game as either a replacement for the zipline on the sniper class or yet another choice to replace the c4 on assault or rpg on engineer. an amazing addition to snuff out those nasty snipers 5 miles away out of range of anything except another sniper rifle or bombarding annoying checkpoints with little goblins camping behind a ridge. an artillery system would be amazing as well but on such small maps it might get a little too hectic.