Why not [Corrosive Projection]? Because it only helps against enemies with armor (mostly Grineer and corrupted, with only select few Corpus and Infested enemies), and only slightly better damage than [Pistol Amp] against armored enemies, and [Pistol Amp] will help against all enemy types. The slight situational damage gain isn't worth the hassle of swapping out all the time and burning an Aura Forma to be able to swap out. Just have a good slash or [Shattering Impact] melee on you and call it good.

Feel free to run [Mesa's Waltz] if you like, but I prefer the added range depending on the Helminth ability.

I have this same mod configuration in each load out, but multiple loadouts for Gloom, Sentient's Wrath, Roar, Silence, Breach Surge, and Quiver (for invisibility, just fire and arrow straight down), or pillage for shield gating abuse. Depending on the situation.

Gloom is great since [Mesa]'s biggest threat is melee attacks and Exilus abilities as long as you have Shatter Shield and Shooting Gallery up, and Gloom really makes it easy to not get hit by melee attacks. Silence is great if you're having more issues with the Exilus enemies since it prevents them from being able to use abilities and staggers everything that comes into range of it.