I disagree - I think Total Civil War (which I'm calling it) would have a very broad based appeal. I'm Australian, and in many respects movies and documentaries about the Civil War have a broad appeal here - and I know they do overseas. It was the first truly modern war, and did witness significant technological change throughout the war. Machine guns (gatling guns), were first used, trench based warfare, modern siege techniques, the first ironclad ships, armoured trains, combined with more traditional flanking action of cavalry and bayonet charges, use of skirmishers, sharpshooters etc. Even the slightest technological edge - such as repeating carbines gave you an advantage. The confederacy also began to put african americans into the battle, too late in the way - what would happen if they had done it earlier? the Turtledove alternative history books paint a picture on how things might have gone.

It combined the best (or worst - depending on your point of view) of modern and ancient warfare. You also had a range of uniforms, unit designations and veteran units vs green 'just raised' regiments. Units would not have a 'good/excellent' morale indicator in their unit card, but would build their morale and combat bonuses more than in the current incarnation of the game.

And they still used significant 'blocks' of troops that would be useable in a Total War engine context. You also have broad brush cultural issues at play, slavery, reliance on trade (so the sea trade has a significant affect on the Confederacy's ability to continue the war against a Northern blockade - hence the invention of the Merimac), expansion into the West, involvement by foreign powers etc. I think the strategic appeal of the Total War genre might have broader appeal than traditional games which are more focused on actual tactical combat.