Tanky Death Knight - help needed

Im currently doing build planning for co-op game. I’m going to play in party with fire\lightning Purifier, and he will be main damage dealer. So I wanna do some tanky build to withstand incoming damage and keep mobs out of purifier as good as its possible, but of course 0-dps character is not a viable choice.
I’ve chosen Soldier as primary mastery (tonns of defensive option), and I am interested in picking Necromancer of Shaman as second mastery as I never played any of them.
Now I have draft of DK build:
But I have feeling that it is over-tanky and will have too low damage output for generating enough threat. Would appreciate any help and suggestions.

Or maybe some shaman-soldier combo would be better? Definetely I need to do some test with grimcalc

If you are serious about tanking and holding aggro, it’s hard to beat a Witchblade with war cry and CoF.