PoE Ball Lightning, psionikangel builds

Hello everyone! I am currently playing a self-cast Archmage Ball Lightning Hierophant. The damage is okay and sufficient for general T16 alch & go mapping. However, when I turn up the notch a little (more juice) or try pinnacle bosses the lack of physical mitigation really shows itself. I can complete most tasks that I set my sights on, it's just that I'll get randomly one-shotted and die along the way, losing a few portals. I'd like to add a little more tankiness to eventually make progress towards level 96 while also being able to moderately juice my maps. With that many unique items