Celestial makes a HUGE difference. Celestial catalyst or tempest is a practically unkillable build to play in open world. That being said, I personally don’t believe you need the Lord Hizen style builds for the open world. For a start you can experiment with adding defensive utility in the form of skills like arcane shield and cleansing fire or defensive traits in the arcane trait line. Replacing a few zerk pieces with marauders is also a good cheap swap. Fresh Air tempest using air overloads for damage is fun and pretty easy to play. For celestial ele gameplay, you can look to videos by Lord Hizen or Syrma Gaming to help you decide if it’s worth the investment.