The ACW scenario should encompass all three theaters, the East, Trans-Mississippi, and the West. With the new trade route system the Eastern seaboard and the Mississippi river will be of vital importance.
I also feel to make things more interesting, because there was no way the South could have won that war. No way whatsoever, because the South simply would not be able to keep up in production with northern factories. The North also had many more miles of railroad in place. What railroad tracks the South did have were made of different size gauge, which meant troops had to be disembarked and reembarked at regular intervals, causing time delays in military logistics. Although this was not the case at Bull Run, but for the most part it would be. During wartime it would have been virtually impossible for the South to rectify this shortcoming.
I may get heat for that last paragraph. If anyone does not believe me, read about William Tecumseh Sherman and what he thought about Southern chances to win the war.
"You people of the South don't know what you are doing. This country will be drenched in blood, and God only knows how it will end. It is all folly, madness, a crime against civilization! You people speak so lightly of war; you don't know what you're talking about. War is a terrible thing! You mistake, too, the people of the North. They are a peaceable people but an earnest people, and they will fight, too. They are not going to let this country be destroyed without a mighty effort to save it... Besides, where are your men and appliances of war to contend against them? The North can make a steam engine, locomotive, or railway car; hardly a yard of cloth or pair of shoes can you make. You are rushing into war with one of the most powerful, ingeniously mechanical, and determined people on Earth—right at your doors. You are bound to fail. Only in your spirit and determination are you prepared for war. In all else you are totally unprepared, with a bad cause to start with. At first you will make headway, but as your limited resources begin to fail, shut out from the markets of Europe as you will be, your cause will begin to wane. If your people will but stop and think, they must see in the end that you will surely fail."
To make things more interesting, if there was a chance England and France to intervene on the side of the CSA, they may have had a chance to win their freedom and the war. Or at least get a better peace proposal other than unconditional surrender. A static ACW scenario with no real chance for the South to win does not sound interesting to me. So, I hope they have thought of a way for the South to actually have a chance to win. Maybe if Maryland and Kentucky had a chance to join the Southern cause, that certainly would be one step in the right direction. Especially, since Maryland was the shortest land route to Washington D.C. Without the ability to move Union troops through Maryland it would have been far more difficult to fortify the capital from invasion and capture. Of course even if Washington fell it certainly would not be the end of the war. Not even close.
