Improve my Marauder build

I have a respec left with my main char, and before using it I was hoping to get some advice from some more experienced players on my build, and where to spent my points at.
I have 4 points still left that I haven't allocated yet.

So my main skill in in my weapon, which is ice crash. Aura is Herald of Ash and Hatred, with a fire golem.

I quite like my DPS (around 30k now), and the area of effect it has. Don't know how good this skill is considered to be but I like it.
I still have a problem with some bosses one-shotting me however :( . So I think of taking more life nodes? Or would armor nodes be better? I have around 53% phys dmg reduction atm.

I am also thinking if I should remove "resolute technique" from my skill tree - because now I cannot use all my elemental dmg, to for example freeze monsters.

How would you guys improve my build?
Thanks already for helping out!

https://www.pathofexile.com/passive-skill-tree/AAAABAUAAASzCZYMXw3NFCAU9hjXGj4a5BynHM4elCE0KS4rUDGeMgkyiTSONZI5DjrhOzs8BTwtPQ89_EE_Q8hPBFBHUeZTpVWpV-JYY1ugXz9nm2hYaPJqAWoEaqVr2WxGcmxyqXZ_dqx3U3flfA58uHy7fNl99X7ggpuDX4PMhjuIj4nYjM-Uh5d5l7SaO55XnsWf36IAplenVa4-r6e0L7Xytz7AZsRYxPbGrsbY15bYvd-y5FHqGO0g7w7vfPAf8kX2SPcy_TD-Cv5U

Ow, I was also wondering if my automatic molten shell chain was supported well.
I am not sure if "increased duration" is a good idea here, because we get less explosions then.
At the other hand, then the extra armor stays on longer - not sure what the most important is here, the extra protection or the explosions.

Some people would probably suggest trying Earthquake and you might even level it and swap it in and see if you like it. However, since you like ice-crash and it can be map viable I just suggest some issues with gear that might be contributing to getting one-shot.

Life: You are missing a lot of life on gear, I mean boots, gloves, chest, rings, everything...you should seek out some upgrades to get 70+ and get 90 on that belt and chest.

New weapon: the dps is a bit low there and it is slow. Try a colossus mallet at about 450 dps if you like maces.

Also, I would check support on ice crash build, it is sometimes good to have a blue socket to swap conc effect and inc aoe.

The protection from molten shell is minimal and the damage isn't great unless you are scaling fire damage. I suggest looking into immortal call set-up with cwdt. That can use Inc Duration well and will work with your warlords mark endurance charges.

without endurance charges armour is very weak. your tooltip phys reduction is only estimate, it is much lower against big hitters