I'm an offensive player. Someone's backyard is about to get wrecked and it's not going be mine! I needs that backyard to grow more troops.
I favor all the classical techniques, hammer and anvil, envelopment, concentration of force, middle positions, tactical flexibility, and a focus on elite, mobile troops. Political considerations should never be disregarded and Plan A should always be a limited wargoal that can be accomplished quickly or abandoned entirely. Like the Paradox AI, I prefer to pick on small fries and wait for good opportunities to take on the bigger fish. On the rare occasion I find myself on the defensive, I go for a combination of defense in depth and chevauchee, because if I can't stop you from burning my backyard, I can at least burn yours.
I would also like to take this rare opportunity to brag that I have read all Seven Military Classics.