White ceilings with light grey walls is one option since both tiles and backsplash have a tinge of grey. Choose a really light grey.

Here are some pictures of a very small master bath I did a couple years ago with hexagonal marble floors. The bath surround and vanity backsplash are a light grey glass tile with white grout. The trim color is BM Advance - Brilliant White. The paint color on the wall I can't remember but it is a bit lighter and less green in real life than in these pictures(computer monitors display greens very poorly). The towels are a charcoal grey. I have the paint code for the vanity somewhere, it is a Sherwin Williams color.

Also, for a bathroom, you want honed marble, not polished. Make sure your installer seals the marble BEFORE they grout or your grout color will bleed into the stone.