Help needed with spark character

It's my first time trying a spell caster build using Spark, and after getting to T16 maps I've found my damage pretty underwhelming for bosses. I'm at a bit of a loss as to where to go next to improve my damage, so I would appreciate any advice from more experienced players if anyone could spare the time to look it over.

I have 3 divines to my name for any upgrades, so please keep it budget-friendly :)

https://pobb.in/VP6S45ct8eUt

I would say follow anime princes on youtube.
Played spark, but it is difficult to understand how to scale it if you're doing it for the first time.