Can someone take a look at my Glacial Cascade build?

Decided to make Glacial Cascade build that does a bunch of fire damage as a league starter.

This is what I have so far at act 6:
https://pastebin.com/XEq9gVNg

This is what I have as the "finished" version of the skill tree:
https://pastebin.com/Be9skFLY

What should I do to make my gem setup more efficient?

What can I do to improve my survivability?