I was thinking about the possible Peninsular War DLC and then a light bulb came on in my head.
What if troops suffered attrition from partisan attacks while in a territory with negative public order (immune in cities of course)?
It might only be historically accurate in Spain's case, I really don't know, but I think it would add an interesting (if thin) layer of complexity to the game's campaign map.
Is this something that can be modded? I'm not a modder but I suppose you'd have to somehow make the attrition effect flicker on regardless of location or terrain, and only when public order is in the red. Seems a bit complex for what's moddable at this point within Warscape, so perhaps not. Either way, it's an interesting thought IMO.