My current build, what do you think?

Shadow Master and Valk. both have random items equipped everytime you cast them, and it depends on the skill level.

Since the differences between Nightmare and Hell is huge, so your build might not work that well throughout. Also, it might be impossible to solo in a 4+ people game.

But, of course, it is not too possible to get whatever you want in the game, so sometimes the gear choices depend on what you can get.