In play:
1: Cast Null Star for damage reduction.
2: Make sure you have energy~
3: Try to keep Molecular Prime going to keep your floaty balls of safety from Nullstar active.

Archon Shard suggestions:

• Two regular red shards (+20% duration gives the max 300% for full damage reduction).
• Red shards for power strength for more Slow.Va (will absolutely screw up Speed.Va).
• All five yellow shards for that sweetass PARKOUR VELOCITY HELL YES. (lol)

Helminth recommendations:

• Dispensary
• Empower
• Rebuild Shields ?

For Speed.Va :

• Replace Aura with Power Donation
• Replace Power Drift with Coaction Drift
• Replace [Intensify] with [Overextended]

Explanation:
Null Star gives 5% damage reduction per orb, and you get an additional orb for every 20% duration you add on. (Max of 90% damage reduction at 300% duration). Previously, there was no way to recast Null Star early, meaning you start with great damage reduction, but when your orbs shoot people, you lose it and then you might get stuck at 5% damage reduction for a while and just be screwed. [Molecular Fission] was a gamechanger when it came out, as now anything that dies under the effect of Molecular Prime renews your orbs.

[Nova] has 125 armor, which gives her 29% damage reduction to HP at base, but if Arcane [Guardian] procs, she has 1025 armor, which gives her 77% damage reduction to HP. This arcane could potentially be swapped out for something else?

Ideally with this build, you would keep Molecular Prime going as much as you can. Between damage resist from your Null Star orbs, [Adaptation], procs from Arcane [Guardian], and the conversion rate with [Quick Thinking], this makes [Nova] a very useful support that has high survivability.

Please leave helpful suggestions in comments~