In this example, I'm playing the Union and I have Grant already into Bowling Green. Off to the west there's enemy cavalry, led by a general. But who?
In the vanilla game, even if you can't get any intel on the opposing force you still know who is leading it or some inkling of what kind of force is there by the map icon. Forrest would still show up as the leader, and the AI's hand is tipped to me. The AI, on the other hand, doesn't know which leader I'm using because it doesn't look at portraits. I don't know if it cares what leader I'm using (I doubt it) but I think this adds to my enjoyment of the game. It gives the AI a little bit of an edge that it didn't have before. I'm forced to do some more intensive reconnaisance on that force if I want an idea of who is leading it.
The way this works, the way the sausage is made so to speak, is by replacing -all- of the army level images with versions similar to their NATO symbols. I made up a symbol for the leader, but the rest of them can use what you already see in the game. Instead of an image of the exact artillery unit, you'd see the artillery NATO symbol. The issue with this approach is that your own units appear the same way on the map. They show up normally everywhere else. This makes the game map somewhat less visually interesting perhaps, but I think it makes playing the game more challenging.
What do you think? Would you rather see the more distinctive unit portraits on the map or would you be interested in trying out the modified versions? I don't know that it would make much of a difference, but the NATO symbol versions are only about 4 kilobytes each, versus 5-6 kilobytes for the stock versions. It might slightly improve performance, but I doubt you'd notice it.
I have an image as an example but I couldn't add an attachment to this post.