I am still learning the game. Not much of a modder myself. I am hoping someone can make a Water Cannon as a Truck Part.
Maybe something that, once per combat, lets you blast enemy mobs at one or two tile distance (melee and throw range). Little to no damage, but stun and pushes them to tile 2 (or they stay there).
Maybe have it cost 10, 20, or more Water just to use.