Chieftain to check / first champion / Barrheavy

Hello everyone,
i post my stats and gear to let u know about my first character. I just done act 4 on merciless and starting to do maps. Final boss in act 4 was very hard and i die few times (solo play).
Im thinking about more hp build, but i dont know its necessary (lot of armor).
Second things is to going iron reflect - its a good idea in my build?

Let me know ;)

https://www.pathofexile.com/fullscreen-passive-skill-tree/AAAABAEDAQHnBS0FPAmWDjwRGhOlFCAUcRo-GlUb-hznHpQiryLiJbwl3ybzKS4qTTWSNug4UzkOPydGaUfiSHhKyFBHVw1XVFivXz9hIWFSaGVqHmo7bpduqm87c2t07XZ_dqx253gNeHp7jHy4fuCCB4TEhNmE74Zgh2qKr4qzkBGTqJd5nleezaQZpDmnMKknqW6plK2NtfK2LLl-wBrFU8YExtjPftIh2L3ZYdl82sHbT9wy37_gw-RR6wnvDvIv8kHynPOb974=

https://www.pathofexile.com/account/view-profile/pruneer/characters