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: https://pobb.in/mIIeHhzvbA7Z

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. What gear should I prioritize swapping out?

2. What's the logic you used to identify those?

3. What question am I not thinking of asking being new?

Any purchase suggestions would be huge. Budget of 3 div and 1400c.

What question am I not thinking of asking, I'll update it.
Thanks!