Tank diana really works!

Okay she is lack of Hard CC and sustain etc but, tank diana deals really nice dmg and can absorb some of the damage taken by her low cd shield. at %40 cd she can spam her skills since her mana costs are really low, by only 1 mana item which is usually iceborn I go, she has 0 mana issues whole game. She can still 1 shot enemy squishies(not as fast as ap diana obv. but she is tanky anyway) and can be an extreme diver. With new buff on her E makes her good figter rather than ap-diver- assassin. Her passive just made for fighting.

I usually go this build,

now what I want to ask, I need some help about build and keystone. I play with thunderlords and 12-18 but sometimes I think grasp would be better choice since I mostly deal dmg from my passive. About the building path, Sometimes I get fed and I start building a little more AP then I find myself playing with typical ap diana build but despite that, if im even or behind little I build this items, and usually get nice mr-armor but having issues with HP. I couldnt find any other builds helpful with tank diana. What can you suggest?

Im really having fun with this build, since I have low hp people think im an assassin diana so they focus on me and cant kill me, next tf they ignore me and i deal massive dmg. Diana is very toxic with this build. She can jump in pretty good range by her low cd ulti, use her E effectively to make a little chaos in TFs and cant die easily while killing enemy adc easily or at least forcing enemy carry not dealing massive dmg in tf's. What I am trying to say is actually describes casual Diana but from what I see and what I can guess, diana 's mission is going 1v5 , killing the target then dying. This is what makes her a good diver right? With that build she kills her target without too many issues and she can survive mostly, she can take towers faster, she can be a good frontliner also.