For Incarnon mode [Bronco]. [Creeping Bullseye] conveniently puts the Incarnon mode at 2.4 fire rate, just low enough to double [Hemorrhage]'s bonus; combined with the [Dizzying Rounds] augment, this results in a critical mass of slash procs that [Shred] through enemies.

You could run [Primed Heated Charge] over [Dizzying Rounds] for that extra base damage (3622.1 vs 2069.8!) and juicy heat procs, but in practice I've found the greatly increased slash procs make Dizzying just a tad better. Also the stun effect is nice, it seems to work at much larger ranges than I would expect, and it chains in Incarnon mode. But try it out for yourself and see what you like better.

Evolutions are largely user preference except the last one, for that just take the Crit Chance boost; it seems to outclass Multishot for damage output, and the Ammo Efficiency one is kind of dogshit, lol.

Secondary Deadhead is a bit more damage than Merciless and has a relevant recoil reduction effect, but it can be hard to get headshot kills on this build when your slash procs constantly steal your kills. Also base reload speed is slow and Merciless speeds up incarnon switching too. Kind of user preference here too tho, you can even use Flare if you opt for heat instead of the augment.