Fourth Vow vs Aegis Aurora for Arakaali's Fang Occultist

Hey all, I am playing HC Xbox and somehow came across some good items; Arakaali's Fang, Fourth Vow, Glorious Vanity, and Aegis Aurora. I'm not great at the game but I like weird minions builds and made an Occultist, got to lvl 85 and now revamping my build to include these items.

I was wondering what would be the better setup between these two;
-Fourth Vow + Glorious Vanity
-Aegis Aurora with rare chest piece

I tried the Fourth Vow setup last night and got extremely tanky to elemental/chaos damage but was still squishy to physical hits. I either have to switch to Aegis or try the Fourth Vow and get much more armour and or grace going. I'm still a bit new to the game and the Fourth Vow was a tricky setup for me to get going, plus its HC xbox, there are very few items.

I'm trying to stick with Occultist because I really enjoy the mapping with her, I also follow CasualDan and that is what he plays, but he is much better than me and has more items so its hard to follow his build exactly.

What would you all recommend to become tanky enough for red maps? Is occultist still viable if I go very defensive or do I have to switch to Necro? Any advice on getting the Fourth Vow setup more tanky to physical damage? Thanks for any insight, I appreciate it.