Maybe a resupply system similar to the "Wargame" series, where units rearm from Ammo Trucks. Plus, you might be able to simulate the evacuation of the wounded throught that and the next day, both morale and casualities wouldn't be that severe.
Anyway, if this gets into the game I would stick only to computing groups of wagons, similar to how cannon batteries currently work.
And this might be a silly idea, but do you remember "World in Conflict" online? Where on a 5vs5 match, one guy managed the Air Force, another the Infanty... Can you imagine having 2vs2 matches in this game where one player controls the army and the other one the logistics? I'll actually be fun only if the logistics system is deep, and that may cause problem on making the AI to use that system.
Anyway, I'm very glad that the developers are having in serious consideration the opinion of the backers.