This is my first ever build, I hope you like it.
Also you can remove 1 forma for any slot with this exact config and everything will still fit.
Allowing you to hopefully match this with other builds easier.

Mesmer Shield

Base Strength: 214%
Mesmer Skin Charges: 12

We boost our Ability Strength with these buffs:

• +30% - 2x Tau Crimson Shard - Ability Strength
• +60% - [Molt Augmented]
• +25% - [Growing Power]
• +50% - [Mesmer Shield]
• +40% - [Sling Strength]

Total Strength: 419%
Mesmer Skin Charges: 25

• 200-216: 12 charges
• 217-233: 13 charges
• 234-249: 14 charges
• 250-266: 15 charges
• 267-283: 16 charges
• 284-299: 17 charges
• 300-316: 18 charges
• 317-333: 19 charges
• 334-349: 20 charges
• 350-366: 21 charges
• 367-383: 22 charges
• 384-399: 23 charges
• 400-416: 24 charges
• 417-433: 25 charges

Danse Macabre

Realistically we wont have all buffs up during [Danse Macabre], with [Molt Augmented] and 2x Tau Crimson Shard - Ability Strength we will take out Ability Strength from 214% to 304%.

Helminth

• Roar - Use Roar for or extra damage. Not 100% necessary at lvl cap because [Danse Macabre] scales of damage recieved, one hit from a lvl 9999 Nox will give you 9M stacks of stored damage, this should kill any lvl cap enemy.
• Nourish - You can use Nourish if you are somehow still running out of energy.

Of note here is that while in [Danse Macabre] you are not able to cast [Revenant]'s 1 and 2. However we are able to cast his 3, if you want you could subsume over his 3. Because your [Mesmer Shield] charges will eventually run out, you need to get out of [Danse Macabre] eventually anyway to recast all your buffs. That is why I prefer keeping [Reave] as a movement option and subsuming over Revenant's 1 instead.

Archon Shards

• 2x Tau Amber - Casting Speed
  This will turn his animation for [Mesmer Shield] from 2.0s into 0.88s (2.0 / (1.0 + 0.375 + 0.375 + 0.5)) with the help of [Power Transfer].

• 2x Tau Crimson - Ability Strength
  To get an extra +30% Ability Strength.

• 1x Tau Emerald - Increase Max Corrosion Stacks
  Increasing the maximum stacks of Corrosion will allow you to strip more armore of enemies and thus do a higher amount of damage. At 10 stacks of Corrosion enemies have lost 80% of their armor, giving them a damage reduction (DR) of 40.25%. Using a Tau Emerald and having 13 stacks of Corrosion on an enemy reduces its armor by 98%, giving it a damage reduction of 12.73%. You can switch the Tau Emerald for any other shards if you have external armor strip.

Corrosive Damage Reduction Scaling:

• 10 Stacks = 40.25%
• 12 Stacks = 25.46%
• 13 Stacks = 12.73%
• 14 Stacks = 0%

Corrosive + Heat Damage Reduction Scaling:

• 10 Stacks = 28.46%
• 12 Stacks = 18%
• 13 Stacks = 9%
• 14 Stacks = 0%

Corrosive + [Corrosive Projection] Damage Reduction Scaling:

• 10 Stacks = 36.45%
• 12 Stacks = 23.05%
• 13 Stacks = 11.53%
• 14 Stacks = 0%

Corrosive + Heat + [Corrosive Projection] Damage Reduction Scaling:

• 10 Stacks = 25.77%
• 12 Stacks = 16.3%
• 13 Stacks = 8.15%
• 14 Stacks = 0%