I'm running something similar atm, but... bat and hatred regen primary? I'm using Evasive Fire (3 shots) and... free slot I guess, I rotate all my skills around in that, getting rid of Hatred fast enough is night impossible with trap arming time and decent stutterstepping while shooting, at least from my experience.
there's also another way to play a trap build, mainly with triple evasive fire, damage caltrops and spike trap.
It's an extra to stack some stun/freeze/immobilize effects on your gear, because caltrops will hit so many times those effects over 5-6% give some consistent CC on mobs.
I like the idea of this build but it's a difficult adjustment to make. It's a totally different playstyle than what I'm used to. Like you said in the video, you end up playing at a slow pace, which kind of turned me off of this build. It got the job done though, the damage was great, and I felt like I had a lot of survivability.