The answer for a possible edition to your excellent mod, aside from a few cosmetic touches, such as uniform and weapon textures, and the addition of 'Vivandière' as medics for the French, is quite obvious; the Second Mexican Empire!! It was created by the Mexican Congress with the support of Napoleon III of France, who attempted to establish a monarchist ally in the American Continent. You could include both the uniforms and regiments of the Imperialist faction, as well as the Republican rebels who staunchly resisted the French and the Emperor of Mexico, the Austrian Archduke Ferdinand Maximilian.
