*This is the [Umbral Vitality] Version of the build which has 1 additional Forma cost. To see the base version, look here.

Swaps:

Energy Siphon:

• -> Corrosive Projection (armour strip to the max for higher levels).
• -> Growing Power (If her 3 can trigger this, would help her 1 recast to be stronger).

Streamline:

• -> Fleeting Expertise (even more efficiency because who cares about duration?).
• -> Augur Secrets (More Strength and shield buff without losing Regenerative Molt).
• -> Primed Flow (if you feel you need more energy reserves).

Power Drift:

• -> Cunning Drift (if you feel 265% range isn't enough...).
• Power Drift + Overextend -> [Cunning Drift] + [Adaptation] (a different form of survivability).

[Umbral Vitality]

[Umbral Vitality] can either be rank 10 will affect the options for the D polarized slot. I'd still swap [Power Drift] for [Cunning Drift] if you swap [Overextended] out, but here's the options for the slot:

Rank 8

• [Adaptation] (Additional Survivability, 10% res for 20s up to 90%).
• [Augur Accord] (180 shields and buffs shield gain from ability cost to 80% from 40%).
• Rank 4 [Redirection] (360 shields).
• Rank 4 [Steel Fiber] (270 Armour).

Rank 10

• Rank 6 [Adaptation] (Additional survivability, 8% res for 16s up to 90%).
• [Augur Accord] (180 shields and buffs shield gain from ability cost to 80% from 40%).
• Rank 4 [Redirection] (200 shields).
• Rank 4 [Steel Fiber] (150 Armour).

I'd choose either [Adaptation] or Augur Accord for the strong damage mitigation vs maintaining shields for this more tanky mod config.

Swap Umbral Vitality

• -> Adaptation (Additional Survivability, if the 3 Forma version was too squishy for you).
• If Regenerative Molt / Contagion Cloud / [Hunter Adrenaline] sound better here, I recommend using the 3 Forma version here or the more Strength and Range oriented build here.