I Agree. I have a feeling Takaya may never reveal what The Advents/Creators look like, and I'm okay with that. Explaining details about ancient, technologically advanced extraterrestrial races while never revealing their appearances is crucial for maintaining an air of mystery, as we've observed with The Advents/Creators possible inspirations: The Firstborn from 2001: A Space Odyssey and its sequel, and the Protoculture from Macross.