Prestidigitation and/or the use of water would solve part of the issue, but I think the dirt levels should change based on how close you are to the enemy and how much damage you take.
No one is throwing dirt bombs at my characters (although that would be an amusing thing to add) but ranged characters definitely should not look like they rolled around in mud. Many times I end a combat with all my ranged party free of damage and they just look ridiculous.
