lich... you are really a glass canon
Post ritual, and with the artifact cloak, a charisma based lich is fucking stacked: 500ish natural hp. 70ish temporary hp (both easily replenishable through negative burst), a bunch of defenses from the unique spells (AC, saves, DR, etc), undead immunities (when they work), an optional 10 dr from the strong bones or whatever it's called lich power, a bunch of free dex...
Pre-ritual, however, you're going to have garbage hp and most of these defenses are less relevant if you die to a babau rolling initiative then sneak farting in your general direction. Undead immunities also cost you a level 7 spell slot before you become one for good.