BUILD SPECIFICS
Duration
Positive duration gives adequate duration for enthrall and mesmer skin stun, as well as for your helminth ability uptime eg roar.

Efficiency
Positive efficiency makes it easier to spam Reave and recast mesmer skin on demand, and even Danse Macabre if you like, but Equilibrium gives plenty of energy regeneration. Enthrall cost is basically free since it spreads and is free on an enemy stunned by mesmer skin.

Range
We use Stretch to maintain a bit of range so Reave has a hitbox width closer to 5m meaning you can hit multiple close enemies, enthrall spreads a bit easier and you can also Roar buff adjacent allies easier. If you don't want to use Reave at all, just swap this for Augur Secrets

Strength
Very high strength helps maximise the Mesmer Skin charges (19 at 313% or 22 at 373% str after Molt Augmented, and even more with additional strength sources such as Growing Power, Zenurik or Madurai), Reave and Roar. You need to hit certain Strength breakpoints to gain additional mesmer skin stacks as the mesmer skin count is rounded up when decimal. Every multiple of 16.6667% strength gives one additional mesmer skin charge and every 50% strength gives exactly three charges. General breakpoints above 300% strength:

301% to 316%: 19 charges
317% to 333%: 20 charges
334% to 350%: 21 charges
351% to 366%: 22 charges
367% to 383%: 23 charges
Flexible Options/Slots
Augur Secrets: This is a FLEXIBLE slot that can be used for Streamline, Natural Talent (if no shards) or an Augment such as Thrall Pact (gives over +600% primary weapon damage at max thralls but is additive to other damage mods).

Natural Talent is good quality of life since it speeds up casts of Reave as well as allows you to refresh Mesmer skin in between casts and within the i-frames given by shield gating. This is however more optional now since you can run cast speed amber shards and you now gain 1s i-frames upon losing a mesmer skin stack.

Aura

[Growing Power] gives one additional mesmer skin charge but requires aura forma
[Corrosive Projection] for minor armor reduction, but especially useful if you run Pillage.
[Enemy Radar] helps track enemies from even further away adding onto universal radar
[Sprint Boost] for run speed (which now affects reave)
Exilus
Up to personal preference, use whatever u like.

Power drift: one more mesmer skin stack
Preparation: For quick missions, allows speed reaving/dansing through a mission
Arcanes
Molt Augmented/Vigor - if you want even more strength for mesmer skin stacks
Molt Efficiency - more duration for thrall and roar uptime
Arcane Energize - ideal for energy regen but not entirely necessary
Arcane Avenger - use in combination with Combat Discipline only

Archon Shards
Amber Shard: at least 2 cast speed shards or 1 tauforged cast speed helps with mesmer skin refresh and reave spam
Crimson Shard: as many +strength as you prefer for more mesmer skin and reave damage
Emerald Shards: 1 tauforged +corrosive stack shards for 98% armor strip, which is only 15% dps difference to 100% armor strip

Focus School
Madurai: Power transfer gives +50% cast speed and +40% strength for up to 20s, which is amazing for Mesmer skin and Reave, in addition to general damage boost