Fortunately, I haven't had any crashes or freezing in combat. But, I do concur about the AI. In my new playthrough I was heading up to Bleak Falls Barrow and my fight both at the Tower and at the entrance was totally different than I remember in vanilla. Enemy archers stayed at a distance and used trees for cover, only to pop out to take a shot at me. I got flanked several times at the Tower as well. I can't really talk about staggering as I don't use melee/close combat often but I can say when I stagger its the same animation regardless of weapon hit (not sure if this is engine limited, although he says in his critique it can be varied).