I'ts still pretty easy, I've played everything from Shogun to this, and I've always played on the hardest difficulty
The difficulty can still go up, don't have a problem with it.
The focus more on battles and less provinces to control is good, never liked a big empire anyway.
The cavalry is nice, AI has improved but it's not that smart, so 2 warlords on a ambush mission will decimate the enemy lol.
It's all in the stalking tactics, all in all, pretty nice.