Some of my favs are checkered patterns, arizona green tea, nike check marks, video game under water levels, windows xp/95 stuff and more!
I really liked the abandoned mall / liminal spaces thing. My favorite vaporwave aesthetics are the ones that have an edge of discomfort.
This post has a good intro to what's appealing about the aesthetic
https://sabukaru.online/articles/liminal-spaces-the-era-of-realizing-false-promises