There's no way to get a build like this to an effective AC. I think CE is a waste.. displacement is a fine idea, but my focus has been on maxing diplomacy for aggro management.
I have settled on power quarterstaves now that I am past level 10 - and a vorpal great axe. Not perfect, but it is still putting out decent DPS while you wait for your '20' to come up. No kamas for me.
I will have to run the numbers on stunning blow.. concerned to see your feedback, but high str+weighted+enhancements seems like all I can do there.