Shards

Very much up to you.

If you want to buff your motes use red strength shards
If you want more duration on critical surge use red duration shards
If you want to be tankier use blue health/armor shards
If you want to buff your primary even more use red primary status shards or purple electric primary shards
If you want to buff your secondary use orange secondary crit shards (enemies always have heat due to [Neutron Star])

I personally use red strength shards as it buffs my other ability based support wisp.

Arcanes

Hot Shot gives you 300% additive crit chance on all your weapons, since we are using null stars with neutron star this is at 50x 24/7.

Arcane Avenger gives a flat 45% crit when you take damage, combine with [Combat Discipline] you have this up almost constantly, and with wisps heal from mote you stay at full health.

If you already have a high crit weapon and want to replace one of these you can use something like arcane acceleration/velocioty/tempo to boost fire rate, something like precision or arachne to boost damage, or something like pistoleer to give ammo efficiency.

If you replace arcane avenger replace [Combat Discipline] with something like [Worthy Comradery] so that your breach surge can also crit.

Flexible Mods

[Constitution], [Continuity], and [Adaptation] are flexible.

[Continuity] and [Constitution] are here because I dislike the negative range from [Narrow Minded], you end up with 1.44 less seconds on [Critical Surge] with these 2 when compared to [Narrow Minded]. Can be replace by [Narrow Minded] and [Stretch] for higher duration but negative range.

[Adaptation] in here for easy damage reduction. If you are fine staying airborne to take advance of wisps passive invisibility than this is not needed. I use it since when maxes it essentially 10x our health pool making the 2853 health 28,530 eHP. This is further boosted by things like armor. This can be swapped for more health, armor, strength, or duration.

The aura is flexible if not using arcane avenger, I recommend [Worthy Comradery] so that your breach surge can crit, and deals damage when combined with [Tenacious Bond] on your companion.

Survivability

With [Adaptation] and wisps innate invisibility from her passive and 2 you are able to live just fine. Higher levels require you to pay more attention to staying alive but for most content in the game you are passively tanky enough to relax. [Adaptation] + null stars gives you 97.5% damage reduction when [Adaptation] is maxed. This comes out to 55,345 eHP with max health from motes, and max damage reduction from [Adaptation] and null stars. 3 tau armor shards can increase this to 221,380 eHP by providing an addition 75% damage reduction for a total of 99.38% damage reduction.

Weapons and Companions

I use a [Tenet Glaxion] on all my [Wisp] builds. Use anything you want, weapons with low crit chance but high crit damage work very good with this.

Secondary use anything you want, weapons with low crit chance but high crit damage work very good with this

For melee I suggest using a [Glaive] ([Xoris], [Glaive Prime], [Falcor]) as you can use them while hover with [Wisp] and stay invisible.

Companion is [Adarza Kavat]. Adarza has a precept called [Cat's Eye] that gives you a flat 60% crit chance for 10 seconds every 20 seconds. This combine with arcane avenger gives you a flat 105% crit chance increase. That means that even if a weapon has 0% innate crit you will yellow crit when both of these are active (orange crit 5% of the time too). This flat 105% crit when combined with the 550% additional crit from hot shot and [Critical Surge] means any weapon with a 30 base crit (an no crit chance mods) will red crit when everything is active. The [Tenet Glaxion] with a base 20% crit chance consistently red crits with just [Critical Delay] (295% to be exact). Make sure to run [Tenacious Bond] on adarza and [Bite] on its claws to also get the flat 1.2x crit damage boost. If you use tau blue shield capacity shards you can use linked [Redirection] on ardarza to get over the 1200 shield needed to run [Reinforced Bond] also (I do not recommend this).

If you do not need the flat 60% crit from adarza then feel free to use whatever you want as long as it has tenacious and [Reinforced Bond] on it and can active them.

Helminth

Null stars over 4 to activate the 300% crit chance from hot shot and the 75% damage reduction.

Use Case

Good weapon platform to get crits out of weapons that don't usually orange or red crit. Is very good with high crit damage weapons. Duration on [Critical Surge] is only 14 seconds though so you need to keep that in mind, have to manage it like wrathful advance essentially.

Extra

Madurai for focus school