There's a lot of great ideas on this thread, but I couldn't help but notice some mix-ups between the themes portrayed in the abilities and the designs for the operator outfits.
• Madurai Suit looks like a bird/Zephyr outfit, yet is assigned to Madurai (fire) instead of Vazarin (wind)
• Naramon Suit looks like a dragon/Chroma outfit, yet is assigned to Naramon(shadow) instead of Madurai (fire)
• Vazarin Suit looks like a genie/ninja outfit, yet is assigned to Vazarin (wind) instead of Naramon (shadow) or Zenurik (electricity/radiation)
Having read the abilities, I'd have assigned them as (from left to right): Unairu, Vazarin, Zenurik, Naramon, Madurai
Regardless, they all look so good, I'd get all of them for my operator in a flash.
In terms of the changes to abilities, passives and the introduction of Void Spiral:
• "Void Spiral: Void Dash + Void Blast" Would require the player to use Void Blast mid-dash, which is not only a hard button input (specially on controller), but also causes the ability to be incredibly hard to position properly (as you're very quickly displacing yourself while trying to cast this). I would much rather see it implemented as Void Mode + Void Blast, or Aim/Block + Void Blast.
• It's a bit confusing how these abilities are distributed, as I understand it each ability in a school's list is a single node? Would this maintain the tree progression system?
• For Madurai's Void Spiral, why reload speed instead of +% fire damage (akin to Ember's Accelerant)? That seems like the type of QoL I'd expect from Zenurik (or Volt's Speed).
• I would've though Vazarin's theme to be "Water" and Naramon's to be "Wind", but this also works.
Those are the ones that really stood out to me while reading through the first time.
Hope some of your proposed changes make it to the game one day!