I really think that it wouldn't be hard for CA to give the AI, specific army designs and specific tactics to use when certain conditions of its armies were met.

As an example, when the AI makes an offensive army after going to war it should be able to make a plan on any terrain on how best to use that army. If it has an army of 5 infantry units, 3 cavalry units, and 2 artillery units it should place them on the best terrain it can find (the highest hill, hide behind a hill if the player's army has cannons and they don't, etc.) Then put their army into a set design, such as a line of infantry with cavalry on the flanks protecting the cannons' flanks and cannons behind the infantry lines.

What I've seen time and time again with this AI is just stupid desicion making when preparing their position on the battlefield. They ignore stone walls and defend open fields with less units. They also seem to abandon any defensive plans once my troops get near them. They will break up their lines, and move their army forward usually one unit at a time.

With the problems the Battle AI has I am at least happy that the AI no longer spends 10 minutes running from my larger army. So many times in MTW they would abandon the highest position on the battlefield when I approached and moved to a lower point in the map so I could attack them from above.

The AI has to be able to find a good (not necessarily best) position on the battlefield and dictate a coordinated defense/assualt based upon the composition of your army and their army. The AI just keep changing its minds when I move my troops.