A great introduction that may answer many of your questions is here:
http://www.ageod-forum.com/showthread.php?t=6823
The "AACW 101" thread by Runyan99
Don't tie yourself into knots because it does get easier once you read through some of this stuff. Couple quick tips that might help:
1. Plan some "Senior Field Trips" - sometimes the more senior generals have to be sent on a long field trip to allow less senior, but better, generals to take command (you mentioned the problem with other general taking command when you combined a stack - now your problem is solved!). Point is just don't keep them in the same region or same stack with your good units - put them in a backwater somewhere, or command a small garrison in a city behind the main lines;
2. Cavalry + river steamboats = fun fun fun! Use a good cav leader with 2 cav units and you can raid deep into enemy territory. Rivers can be blocked by manned forts, enemy ships, or land stacks that are deeply entrenched with artillery so you have to avoid those blocking points. But think of the river syatems as the autobahns/freeways that allow you to strike deep into enemy territory. You can capture small amounts of supplies that will keep your guys well fed, but don't get into a major fight (use the "evade combat" stance);
3. In reverse #2 = pain in the arse! So look to protect your own rivers and block raiders with small flotillas on combat mode, forts with artillery and always have a reaction force ready to go after the bad guys when they show up. [I'm paying a game now where it's late 1862 and I'm still chasing raiders around in parts of southern Iowa and northern Missouri because I did not pay attention in the west - bastards have taken Omaha, and even tried to go after Denver...the AI is getting smart about making me waste time and resources chasing them down)
3. Leadership is crucial - learn the importance of the 3 ratings and use the good leaders to your advantage (e.g., General Dix is great on defense so use him to command Washington or some critical garrison like Ft. Monroe)
4. As the US don't industrialize - early on I made the mistake of industrializing (building new factories to create war supply, ammo, food, etc), and did not understand that you pay the costs of industrializing EVERY TURN...so don't do it unless you have scads of money and you want to bring jobs to your consituents in West Virginia or something.
5. Build rails and river transport - moving supplies to the front is important, plus you always need to move those artillery units by train or river cuz they take too damn long to walk on their own!
6. Lastly, & most important: think offensively, but fight defensively. Read Arslans' thread and he will explain it in detail. Bottom line is to move your armies to take key positions, then hold them and make the enemy attack you when you are rested and dug in. Attacking with a 2 to 1 odds in manpower is crap if you are disorganized and he is entrenched. Think Malvern Hill, Fredericksburg, 3rd day at Gettysburg...and use it.
Good luck!
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