As for villains, Loki is cool, Zenians seem neat but maybe give them like a few more animal-like features to make them intimidating, and maybe give Xanthiel a new albeit similar royal armor to make him stand out.
zenians do have some animal features like hooves and a third arm that are hard to translate into the artstyle
but yeah i do understand the complaint with xanthiel
this is more of a casual outfit for him since he just sorta chills until like the end and is mostly a supporting character
he does get progressively more pissed off with their mistakes though
he snaps in episode 9 where the heroes accidentally cause a chain reaction destroying zenian home planet in order to save earth which makes him decide to execute all of them, ordering all zenian life forms (including civilians) to do EVERYTHING in their power to kill them or else they will be executed as well
