Thank god for the retrofit mod. I had no idea this expansion did squat to the grand campaign, I couldn't really care less about the added ones.

I would recommend the Retrofit mod without reservation, for little more than the balance changes. You will be overjoyed to find that peasants are now the entirely useless cannon fodder distraction they should be (the next lowest unit, Town Militia, will mince them), and while cavalry are still relatively powerful, they do not simply chew through anything and everything they can make a charge against.