Need advices about my CWDT Chieftan

Hi guys. Im using CWDT Chieftan build, you can check it in my profile, its my only one char inHarvest league. aneed some advices tho.
1) its very hard vs dangerous bosses. Cause i need to stay and tank their savage dmg to even start damaging them and cause they are alone - my cwdt procs are pretty low and im dealing low dmg while also risking life. Im tanking 25(30) self dmg tho with each ignite, so maybe i need to find some fast attack/spell which i can use with no links just to target focusing boss with selfcast to proc consistant amount of ignites? but which skill to use? firestorm isnt reliable - bosses often not stay still....maybe cyclone? but i dont have AS.... i can ignite with any spell/skill, has alot of fire dmg and like 80-100% ignite chance.
2) which bosses are immune to ignites? i fought Hydra and it felt super hard and slow... dunno :(
3) What i can improve? Im having like 6500 (planned 6700) hp, but still vs some bosses it feels oof. afor example vs Poison green atlas general....his snakes from the middle hurts alot :D if i stay - they just kill me.
At clear this build is super ez and fun, but vs some bosses i need to find something....cause without reliable ignites i has no life regen and not much cwdt procs=not alot of dmg.
I dunno, i know CWDT sequence is important, cause spells from some items goes first (like, gloves and boots are last, after chest) or maybe my link sequence is wrong?
:( ty for any advices