In the BattleLog, if you have loose units as you mention in an Army stack, then the report will list the Commander and the Unit Commander in each battle round. Small units like Artillery Batteries might be led by Lieutenants or Captains, Regiments by Colonels and perhaps for game purposes, Brigades too.
The rank icons are somewhat smaller in the latest patch. If you click on a stack and then cursor over the stack on the map, you should get a pop-up menu with the officer's names and by their namesw either three gold stars, one silver or two gold stars.
I'm the 51st shade of gray. Eat, pray, Charge!