You are all neutral so you can pick any color you like for accent. How nice you can change things up occasionally. Try picking up a few dish towels in several different colors, lay them on the counter and pick the color that grabs you. :)

Mine is similar - I found art with white, charcoal and pears, somewhat bright green.

Palette shows grey - and soft yellows for accent idea, or toward apricot / peach...

Yellows.jpg · More Info

Look around in your closet, in your magazines, at your art - sit things by tiles and cabinets, and see what strikes you! One of my likes / would you like a soft teal?

Gingko by Albert Koetsier · More Info

That is a neutral kitchen. I'd go to Home Goods, Pier 1, Bath Bath and Beyond and anywhere else to pick up colorful items(jars, bowls, candles, artwork, etc), just to see which color would work. You do not have to keep the items, you just want to get color ideas. Try colors like greens(different hues), oranges, yellows - warm colors.