At 70 you need to start switching up your gear affixes because armor turns to mush in high NM dungeons.
Defense
- X damage reduction
- Damage reduction near/close
- Health/Rubies Maybe some Topaz
- Dodge
- Damage reduction while injured
- Jewelry gems should switch to resistance when you are fighting 17 levels above because by that point your armor is effectively gone. Focus the elemental types you die too.
It’s still going to be rough, but this will make it a lot less rough until season 1 starts.