Those are vanilla armor settings on all difficulties if your actually an Ethereal Commander. However, as an actual Ethereal Commander I can assure you that we do not have 116/87 Psy. We have 75/58 on superhuman. Are you using a re-balance mod? Cause I think I like it.
Just consider it a force field that the ethereal surrounds itself with. It's just a (really) skinny dude in a robe, so thinking of it as physical armor does not really work (unless you think the robe is made of adamantium, in which case under armor should be 0 ).If they can fly because of their psychic power, slowing/stopping bullets does not seem like that much of a stretch (applying a force to a bullet to slow it down from applying a force to yourself to cancel gravity is not that different)