Evolution I: Headshots charge Incarnon Transmutation; Alt Fire transmutes. Switching back will expend any remaining charge.

Evolution II: Perk 2: Crimson Overture: Increase Damage by +12 (Boltor) / +2 (Telos / Prime). On Kill: Increase Damage by +2 and +20% Ammo Efficiency for 5 seconds. Stacks up to 3x.

Evolution III: Perk 1: Swift Deliverance: +60% Projectile Speed.
This is personal preference.

Evolution IV: Perk 1: Elemental Balance: Increase Status Chance by +20%.
Commodore's Fortune is also a good choice, but the riven makes up for it here.

Galvanized Aptitude only works off base damage and is not affected by Crimson Overture