I suggest using:
5 Archon Crimson Shards to get 400% power strength (can use less if Tauforged), this way Pillage can 100% armor strip. (needs to go to 340%, then Molt Augmented gets the last 60% at 250 stacks)
Casting speed would make 1 go out and return faster and you can cast Thermal Sunder faster, these two things are HUGE. So if you could use 3 Tauforged Crimson Archon Shards with ability strength, you have 343% power strength and 2 slots open for Amber Archon Shards with casting speed.
(Could also do 1 tauforged, 3 normal and then 1 with casting speed)

ABILITIES:

Elemental Ward with electricity (damage [Reflection] works when casting Pillage) or Thermal Sunder.

MODS:

Could also use [Corrosive Projection] in aura slot. You need 328% ability strength with [Corrosive Projection], so with Molt Augmented, you can actually avoid having to use any shards at all. But using those shards for strength also adds damage and more buffs to Elemental Ward + you then have place for something else in the aura slot

COMPANION:

Hound for more nuking and CD Shield Hound