Maybe you think this is just for fun, or this is a troll build. But really, I had use this build for [Mesa] for over 150hrs of overall playtime. I really enjoy [Mesa]'s Peacemaker and I really like to improve it as much as I could, although this make her really weak at survive in exchange.

For Aura mod, you may use whatever Corrosive Projection/[Energy Siphon], just use which is better as you thought.

The Streamline mod can be changed whatever as you wish. If so, I recommend change into Primed Flow for a Forma, or Umbral Vitality/[Umbral Fiber] for a Umbra Forma.

For ability, I had change [Mesa]'s Ballistic Battery into [Rhino]'s Roar. If you haven't feed Helminth with [Rhino] yet, you may use Helminth's Empower instead. For Empower, I use my skills order like this : Empower>Shooting Gallery>Empower>Peacemaker. This is quite energy consuming and the attack didn't increase as much as Rhino's Roar, as Roar increase attack for 101.1% in this build.

For Regulators Build, please see it here :
https://overframe.gg/build/78611/regulators-prime/overpowered-regulators-build/

See my other build of Mesa for steel path :
https://overframe.gg/build/131931/mesa-prime/mesa-for-steel-path/