The Dark Bronze Metal looking structures with light bands around them and the nice highlights along with the Bluish/Green Glass on Post #7 has more of a Space Colony look. The Colors, highlights, Dark Bronze Metal and Bluish/Green Glass help to create a Space Colony Feel. A Smooth Glass Dome also appears more like a structure that would be used in space.
I realize you are still in progress and experimenting. I would avoid the use of Pretty Pastel Colors as they will create an appearance on an Earth like modern structure.