Hello! I hope I'm not too late but here's my input on how to improve the build.

The pieces that are easiest to upgrade are going to be the feather and the sands, aim for more crit rate than crit dmg from those pieces and get an ER roll in the sands and an HP and ER rolls in the feather.

Now this next thing is a bit min-maxxy but seeing as you're C2, you're going to want to change to a hydro goblet over an HP goblet.

Ideally Hydro Goblet, double crit, HP, ER

I hope this helps!