How should I update my character to do Ultimatum stuff?

I like Ultimatum for some reason and I think it would be fun to have an atlas tree focused on Ultimatum. I've never actually stuck with a character to 100 before and I thought updating the one I'm playing this league for Ultimatum and just general survival would be a good idea.

I need to get a better helmet, boots, and ring. I also need better jewels and a new belt, but I at least have that part figured out. It's just the things I want are far too expensive to justify doing them first. I guess I just need a sanity check before I spend a bunch of time making new stuff.

I need some way to deal with physical damage. Right now I have some armor (10k with combat buffs) and low evasion/blind, which solves low physical damage. Petrified Blood, Dissolution of the Flesh, and Eternal Youth stop most damage, but I need something to stop high physical damage.

Is there some better option I'm missing than just going full ES with rare Lich Circlet and Warlock Boots?

There's also passive tree stuff, but I feel like there isn't much point in changing that around until I get the new items.

https://poe.ninja/profile/Ghin-5436/character/GhinPact

I've been looking at other people using Relic of the Pact and I just find some of the choices baffling. I've been messing about with different gear and tree configurations to try to optimize things a bit and make things more comfortable. When I try out other people's builds in a random alched T16, I almost always die before completing it.

I see a bunch of people using Lifetap just for the reservation without linking Lifetap to another skill to get the damage bonus. If I use Lifetap, it means I can't do damage if I get hit even a little bit. Whereas when I use Awakened Brutality + Second Wind + Critical Damage, I can get to the second tier with a short click or spam the first tier in situations where I am taking damage.

I also see people using Pride. Which okay, it adds good damage, but I feel like it would be better to use Hatred and convert Physical to Cold to freeze everything and get higher damage. But if I switch out Petrified Blood and Eternal Youth for Pride or Hatred, I can't really survive being hit. I'm not seeing how I could level like that, I would be dying all the time. Like, even with a Mageblood I still feel like it wouldn't be enough.