Transonic Blades & Arc Rifle Electrocute build (Vet+)
 Skitarii Build - Warhammer 40k: Darktide 

Primarily ranged build built for the purpose of target removing Elites and Specials as quickly as possible without succumbing to the horde to keep Galvanic Marking Array, Hybrid Combat Covenant, & Moebian Conductor up as much as possible.
With that said, using your melee weapon to keep Hybrid Combat Covenant by continuously clearing horde is important, your servo skull firing into the horde will keep the other half of it up while you do so.

Almost anything that doesnt die just by looking in its general direction will fold pretty easily to Chordclaw Strike, i use Satiated Steel because it stacks with Flux Conduit Build-Up & Reactor Coil Recharge which gives you a pseudo 4th ability charge for dumping all 3 stacks.
 

i find that the other ability modifiers that change the attack just make it a substantially worse panic button. 
(maybe taking Axial Slash and using it as super horde clear and getting mad capacitance regeneration off Satiated Steel is a valid move but i dont think Branx Mk XI Paired Transonic Blades are particularly lacking in horde clearing capability so in my opinion Axial Slash just makes Chordclaw Strike almost useless against Crusher, Scab Mauler, & Scab Plasma Gunner for almost no real benefit)
(and Probing Strikes is just straight up bad IMO)
 

Medicae Servo-Skull is probably the most powerful ability in the entire game, and the other two blitz's dont even begin to compete in terms of utility and overall impact on a mission. 
If Integrated Refraction Emitter gave you some kind of melee protection outside of Kinetic Repulsion it might compete with the servo skull, but it doesnt so it doesnt. And Arc Grenades are just a laughably selfish choice when presented with the other two.
yes these abilities have their purposes and they fulfill them well, but being able to prevent someone going down at the wrong from cascading into a team wipe at the cost of 1 grenade charge and just the time it takes to look at them is something that cannot be understated.
 

Between Ammunition Deposit & Resurgence the choice is yours, the Skitarii skill tree has so much Toughness Regeneration that i dont think Resurgence really makes the cut so +10% Ammo just feels much nicer.
 

If toughness regeneration becomes a problem for you, you can swap Assassination Protocols for Entropic Transfer.