Make the guns more expensive, especially the musket.
Make the soldiers less stupid (Stop them shooting their own team)
Make it so that you can command the soldiers to stay.
Make a recruitment charter that lets you recruit soldiers without having to go and find them.
More soldier types.
Maybe expanding the mod to not just include the civil war but also the Napoleonic wars and stuff. (Could work with the new soldier types for soldiers like some of the ones from Empire and Napoleon Total War.)
If you need textures, I have got some.
Great ideas! I can include them in the next version, although it will take quite a while. As for that last idea, I've got an idea in the works kind of like Millenaire or Civilization Revolution. It will be a seperate mod.