IMO, some variation on beige/tan is the only appropriate color for wall-to-wall. Go to the store and either bring home samples or ask if they'll check out the sample board to you (you generally put down a deposit and they give it back to you when you bring back the board). Find whichever beige/tan sample goes best with your wall color.
DO NOT install gray wall-to-wall. Gray is the hunter green/maroon of the 2010s. And it'll make your home seem as cold as ice.