i agree; it is more of a semi-tutorial than serious campaign up until chapter 3. still, it should be easier than the others.

also:

unfortunately, this is true with just about every single game with a.i. they send everything they have, then either: dont produce units OR continually crank out units, but send them out in 1 and 2-unit armies constantly. together, they could be a serious threat every few turns. however, they dont do this so..................