Under difficulty settings in General.opt do you know if you can have non integer values - e.g. 1.5 or negatives? The similar thing in Hearts of Iron was a combat modifier set at 20%. So going from normal to easy gave +20% bonus easy to very easy +40%; going from normal to hard was -20%.
Can you have AI with fog of War, player not? I guess I could play around with these myself, but there is a high chance of mucking up.