Good suggestions. I really like the idea that issuing too many orders causes stress and morale drop.
Personally I think would like command delays, and command signals could be accurately rendered with flags and runners, etc. It's a little problematic though, depending on how you see it. On one extreme you could be playing the general, and only be able see what the general can see, even hiding your own troops in fog-of-war. The other extreme is that you're omnipresent and that you "are" all unit commanders simultaneously, and able to see what they see and control them instantly and all at once. The first one conflicts with playability (unless you're really hard core), and the second with realism and fog-of-war. I think one has to find a good compromise, where players are omniscient about their own troops, but with fog-of-war about the enemy, and a balanced amount of friction.