I have been thinking on kenetic damage on ground missions. So far the only real kenetic damage comes from engineers mines and tacticals grenades. Mines and grenades....limited to character type. What about adding shoulder fired "micro-torpedo" launchers. They would work like modern day RPGs. They can come in the same types as the ship torpedos. They can deal maybe slightly more damage than the grenades. Seconadry fire could be equivilent to THY1 on the ship.
Another idea would be an energy weapon that has a grenade launcher for the secondary fire. Akin to the M204 used by the US military. Grenade type would depend on energy type.