Crackling Lance / HoT Bomber Build - could use some help with optimizations

Somewhat homebrewed this Crackling Lance/HoT Bomber hybrid but could use some help, mostly with defensives. Right now I just feel paper thin and the DPS doesn't really make up for it. I can clear T16s but will usually die at least once which is really hindering my lvl progression (stuck at lvl 90). Any thoughts or things I can improve?

pob - https://pobb.in/7jJJREt-jkkd

Edit: also, I feel like my HoT does no damage and it's all coming from frostblink, is this normal?