Alright, Im playing the same build and here what u can improve:
- Improve the wand, its your main dmg contributor. "Gain as X" is direct multiplier, so it will give a lot more dmg (aim for 2x25%+). Try getting crit chance as well.
- Socket wand with +1 to all spell skills
- Upgrade skill gems! They need to be 21 (+1 from corruption).
- Level up! PoB shows you are only 78, 12 more skillpoints is a lot.
- I didnt find Rakiata being good for anything but arbiter of ash. Most of the monster and map bosses have little to no res, but even if you get tanky ones, maxed out Elemental weakness is way better. In addition, rakiata is only in CoC slot, meaning spark doesnt get this buff and deals way less dmg to resistant bosses -> triggers CoC way less often -> way less dps. El weakness doesnt have this problem.
- Replace Blink (if you have trouble clearing T6 you dont even need it lul) with Charge Regulation (dont forget to anoint Infusion of Power on ammy). Latter gives multiplicative(!) crit chance increase. Having 100% on Spark is crucial for triggering CoC (yours is only 60%)
- PoB shows you actually have 1 empty jewel slot
Also in PoB you need to put "arc deals 200% more damage" in Configuration->Custom Modifiers, because it doesn't count arc's light infusion dmg increase for some reason. And in Configuration->for Effective DPS put "Shock stacks" to 2 (because you have Strike Twice asc notable)
UPD: quick PoB comparison
https://preview.redd.it/w8fewddd95ig1.png?width=592&format=png&auto=webp&s=dc7c66053bc9285b2686a425170923d3bbbce727