Greetings Shark!
First of all thank you very much for your detailed reply. I will definately be incorporating several of your ideas into my campaign.
What I am basically looking for, is not necessarily a "miniatures wargame" version of D&D, but some sort of system that allows the PC's to actually make decisions that have a long term effect on the battlefield. I would like them to be part of the battle plan, and then once the battle begins, to have a way that their decisions can shape what their army will do in response to the enemy. I also don't want it to bog down the story part of the game.
This major battle is several months off, but it will be the culmination of my group's "non-epic" campaign. They will be around 18-20th lvl, and basically put in charge of a large portion of the North's defense. They will have their own portion of the defense force under their direct command, and I want a smooth and easy way for them to direct their troops strategically, while we switch back to the tactical versions that we play out as standard D&D combat.
I will take a peek at the Quintensential fighter's mass combat system, perhaps it will suit my needs.
Once again, thanks for your inputs, your campaign ideas give me inspiration!
TLG