OK, via our discussion I have some more ideas. So someone at the corps level has directed a unit to attack a given position. That bastard is probably asleep right now. At this point say it’s 1905. The top level Army commander has allotted weapons to your unit. Maybe some caried level action 44’s with limited range, but great up close damage, a few 1897 remington shotguns, and some 8mm bolt action rifles. What ever number of weapons thats how you equip your troops.
So playing the FPS, you of maybe 3 people are playing within a platoon of 40. As lead layer you can distribute your real players and the rest of the AI along your skirmish line.
The human players, once they are killed can take over an AI player (until there are no more left or until victory).