One thing you're forgetting that isn't directly stated in the game yet (so its absolutely an understandable thing to miss) is that Revivify can only bring you back up to 1 minute later. By the time a party member fights he tadpoles influence enough to kill it, you're gone to the plane eternal. Now the robed dead man seems to have a more powerful spell at his disposal, so you have a point there. Also, your vamp friend can kill you at midnight while revivify can still bring you back at 6am so point made for you there too. This will be ironed out, I'm sure. The other element is that you're under some sort of divine/arcane/evil machinations that are stopping the progression of Mind Flayer-itis. Who stopped you from bonking your dome at the beginning when you fell off the ship? Why can't anyone remove it? Why does it have a protection method even a Mind Flayer doesn't understand? There's far more at play here than the other True Souls have experienced.