PoE Remarkable-Ad3492, Fire builds

TLDR: I'm not sure where to spent currency and have hit a wall in some content. I have a budget of 3 div and 1400c to upgrade the attached POB. Any advice is more than welcome! POB link: Summary: Hello! This is my first league, and I used a guide to clear 100 maps. At this point, I've hit a content wall in bossing. A Maven-empowered conqueror or delve 200 crystal king are running me over. I'm getting better at dodging, but don't think mechanics will carry me through ubers yet. Which brings me to a few questions: 1.