Need help- Tectonic Slam Scion

Hi, so i saw this skill and thought it was fun, i'm enjoying using it but i feel i lack damage for the price of the items i have, i have a gladiator lacerate/bleed and for half the price it does far more damage and tanks far more.
So what do i do? how can i improve it? im lost at this point, was Scion a mistake? should i go Jugg?
I appreciate any help since i really don't get my mistake here.

POB: https://pobb.in/luZfP6VHrhvP