I agree with the lighter cabinets for the upper and the darker for the lower. I really love the look of this tile for your backsplash but there is no info given, therefore, cannot tell you what it is. http://houzz.com/photos/653687

You should be able to bring a sample home - leave it in the kitchen for a couple of days to see it in various lights - if *you* like it then it "compliments"

HI... always lots of decisions when building a new house. When working with a neutral color palette- adding a material that provides contrast is always visually interesting. If you plan on adding red accessories- gray would certainly work. You could use a solid color quartz material or even Vermont soap stone which is inherently gray. Shades of brown with red and cream is also quite pretty. I just snapped a photo mixing some materials from a project in front of me-- this is arrowroot (the stone) and you can see on the fabric motif how pretty it is-- the brown and red next to each other in the fabric pattern. Hope the photo came through. Hope that helped.

Sorry I overlooked your question about the island. I don't know if it should be a contrasting colour because as I see it, the main feature of your kitchen is the gorgeous range. If you paint the island to match it, then the range will lose its impact. If it were my kitchen, I'd match the island to the other cabinets. If you were starting over, you could have had it made in stained wood, but with it already existing it requires a painted finish.