I don't play it at all now. It's a frustrating mess and attempting a campaign is almost unbearable especially when you have to sit for ages even on fast forward while the AI slowly, so very, very slowly tries haplessly to climb about four ropes to get through your defenses. It's painful and depressing. I've totally given up on this game and I'd be willing to bet everything I own that the patches will soon stop coming and once again a Total War game will have failed to achieve its potential except this time more spectacularly than ever before.
Medieval 2 is and will undoubtedly continue to be the pinnacle of the series for me and that's what I'm playing at the moment. I really had hope for Empire. Bought the Special Forces edition and the DLC to but now I give up.