I have a creature in my story that I have a name for, but I'm not sure how I want to spell it. He's worshipped and revered as a god-king on a planet of primitive beings. He's disguised himself as one of them, but he isn't. He's the most technologically advanced alien humans have even seen, the most powerful being in the galaxy. He's the only one of his kind and more than a billion years old. For all practical purposes, he's all powerful. (Think Q from Star Trek minus the ability to travel through time.) So I named him after the king of the gods, but yesterday I had the idea that I should spell it differently, so which do you like better?
'Zeus' does just make me think of Zeus, and I'd only not be annoyed by it if it's a name given to him by the humans and his real name is something else. 'Xeus' smacks of just not being confident in the name, but too committed to change it. 0.02$
If you want me to say "Zeus" in my head when I read it, then spell it that way. The X just smacks of look at my cool spelling! If you spell it that way, I'm going to say "Ekseus" in my head just to be contrary. Interesting to note that Zeus is etymologically related to Dios (Spanish for God) and deity. Wiki gives some interesting options that are less trodden:
I like Dios. I would avoid calling him Zeus unless it's a deliberate nod in the book--like he tells them to call him it because it amuses him.
