Hello LincRead,
Sayyyyyy, this might be out of your intended scope for the game, but I have some suggestions. Have you considered adding the ability to redirect the flow of rivers, and other similar terra-forming to destroy enemy towns? How about salting the earth? Plagues? Famine? Inclement weather? Locusts? Natural disasters? Mud that slows your troops down? Awesome game so far!
~Villager