I've witnessed in my games, and seen on this board, a lot of problems with southern raids deep into northern territory. I'm not going to rehash the rest of what has been said, but I will mention something I haven't really seen talked about before.
It is ludicrous how fast these southern forces are moving through the Appalachian Mountains in West Virginia. It was physically impossible to move with any speed through the Mountains in West Virginia. There were virtually no roads, most ridges were impassable for anything except foot traffic, or very slow going horse. It was impossible to move wagons, supplies, artillery pieces, anything heavy through these mountains. Even on the few roads, they were so easy to bottleneck, with no alternative bypasses, that a few soldiers could delay large numbers for months if they wanted.
Yet I just saw Joe Johnston march from Morgan WV with infantry, supplies and artillery, go four regions, attack and capture Grafton West Virginia and then keep moving.....all in one 15 day turn!
Absolutely ludicrous. This is something more accurately out of a WWII panzer blitzkrieg than it is from the Civil War. I think a lot of the frustration people are having with the raids isn't so much from a lack of garrisoning as much as it is this super-highway that exists where impassable mountains exist in real life.
A unit should never be able to travel more than one region in a turn in the Mountains.