Thanks for sharing your gear list.
Since your going poison have you thought about using dead keeper set instead. You would need to use clouded dreams to get your crit back, but its very posible to make a gear set with that. deadkeeper set also has light armor so you could use that to up your MRR cap.
I have in the past been quite challenged by reapers, this epic life im going to use legendary salt in my off hand to help CC them.
Have you considered going fire instead of poison? Fire allows emperian magic for 10% more universal crit chance. I'm also having good luck with cindersmoke.