I'd like to see the ability to take some of your enemies' heads after battle. "Celtic warriors would cut off the heads of their enemies in battle and display them as trophies. They mounted heads in doorposts and hung them from their belts. This might seem barbaric to us, but to the Celt the seat of spiritual power was the head, so by taking the head of a vanquished foe they were appropriating that power for themselves." [source] It would be cool if you could take some heads, stick them on poles, and place them around your city. Maybe this could do something like increase your own army's morale or lower invading enemies'.
