The battle planner is truly one of the most exciting new features of the game. It has so much potential that is not being realised yet. Battles are currently too static. There should be room for manouver: with the right combination of troops and high initiative leaders. I am thinking of Jackson's march around the Union flank at Chancellorsville or Van Dorn getting in behind the Union army at Pea Ridge. As Napoleon said "manoeuvre sur la derrier" or Patton: "hold 'em by the nose and kick 'em in the ass". This could be reflected more accurately in the game and it would give the Confederates with their more audacious leaders the historical advantage they possessed early in the war.
Another addition that would truly enhance the battle planner is the addition of flanks and a reserve. Currently all we see is the general in charge of the entire battle. However, in reality the medium to large scale battles had senior generals (usually corps or divisional commanders) in charge of the flanks. It would be awesome to assign generals and separate tactics to each flank, the center and the reserve. i know this might be a sore point for AGEOD but the way you can set up your army and tactics in "March of the Eagles" is the direction that this game should move towards... and why not surpass it?
My final recommendation is to slow down the battles so that they are more enjoyable affairs. Then the player can see the impact of the tactical and command decisions playing out in the battle. Obviously small skirmishes would play quickly but the larger set piece battles should feel like significant events and be memorable. After all, for this old war gamer all of the planning and manouvering is about getting to the battle: therefore the battles should be more detailed and more exciting and involve more choices and input from the player. Currently the way the battles play out and the battle report screen doesn't do much for me.
Like I said, the battle planner and the actual battles themselves have HUGE potential to be one of the most exciting and rewarding parts of this fantastic game!!!