Help request: Where do I go with my build?

Hey guys,

I am looking for some help/advice on how to continue with, improve and better my build.

I am relatively new to PoE build making and started playing the game in Settlers, but really put my time into PoE, as PoE1 still feels like too much too grasp at times.

Every league I try and make my own stuff work, usually they crash and burn somewhere around T15s, where I switch over to a buildguide to continue with the rest of the league. With all the lessons learned so far, I am getting better and better every league, but now I am hitting a cap I have not encountered before.
My mapping is fairly ok, for me atleast, with clearing not being a massive issue. It is not the fastest, but I barely ever really get stuck on a pack.
My main issue now comes with bosses, they just die so incredibly slow. It seems to be a mix of not having enough damage and having too dodge too much to comfortably deal the damage.

I am open to any input/feedback on how to overcome this next barrier!

Build concept

PoB: https://poe.ninja/poe2/pob/1537c

The build idea was a fire bear, not original, I know. To make it work I have largely gone into fire damage scaling and Avatar of Fire. I am purposely not going for the Fury of the King jumpy build and am trying to stay away from too many weapon swaps (It just confuses me, honestly).

The playstyle revolves around building glory by being at max rage (Walking Calamity) and by ingiting enemies (Ancestral Cry). Maul is used as a basic ability with Furious Slam as a filler on rares/bosses.

Main struggles

Bosses in various forms:
- Azmeri spirit possessed
- T16
- Tier 3+4 pinnacles

Death related issues:
- Degen mechanics (Abyssal)
- Large physical hits
- Full clutter screens

Goals
- Comfortably mapping decently juiced T15-16 maps, without struggling on bosses
- Collecting all the atlas points.

Like I said, any ideas/help are welcome!