You have plenty of light tones in the room, with the darkest being the walnut. You need a bit more dark tones to ground the room. I'd look at something like a Coffee Brown Silestone with a Silgranite sink in the dark brown color. And don't forget to add under cabinet lighting if you don't already have it.

Or my other thought was something in a green granite.

Verde Butterfly
{{!gwi}}
Tropical Green (my favorite of the greens)

Or even the inexpensive and more common bulletproof Uba Tuba
{{!gwi}}

with the 2 different cabinets-both on the lighter side I would find something with beiges/whites playing off each other-with some darker pieces of color mixed in, whether green/brown/coppery/gray/black. It would end up looking medium intense rather than really dark-probably better to tie the 2 cabinet shades together.The amount of movement is just personal preference...some movement at least would be better i think. This can be really pretty.

Take a hop over to home decorating and look at ksue's post on helping her find a paint for Giallo Napoleon. Green designs shows the granite next to light and dark woods. Another poster shows her light and dark kitchen with Giallo Ornamental granite.
I think we need to see pictures of what you have and we will be able to give you more ideas.
Also, have you looked at the Finished Kitchen Blog that GW has put together. It is divided into granite types, kitchen wood types etc. There is even a backsplash slide show.

I like the brown tones with the natural maple, but with light natural maple perimeter cabinets, the island being also light but in white is throwing things off. You need a different color. And it can't be dark, because you are using the walnut on the island. Is the island in poor shape? Why not just paint your existing island rather than replacing it?

Willow Green Island with Walnut,

green design: Thank you for taking the time to put those color swatches together it helps so much to have a visual reference. I never thought of going with browns but it does look very pretty together. I love the brown sink. Love it. I lean more toward the brown shade than the greens I think. Where are those round tiles from and how did you kick all this out so quickly? Wow.

herbflavor: I am drawn towards light countertops...or really dark countertops. See how I work? My favorites are natural soapstone (but the price for that in Idaho is through the roof and with 4 kids I think the chipping would kill me) and the white shades of caesar/silestone.

ellendi: I'm going to try and figure out including photos today but I have my doubts...I can't even figure out how to find my own posts. Thank you for the suggestion to look at the finished kitchen blog..I'll go there next and it will be new to me.

livewire: Love the paint swatch you included, so warm. We are replacing the island because the current one is too small and I have been jealously watching my friend pull out her giant, perfectly organized, full extension, soft close ikea drawers for far too long...only to reurn to my dark cavernous holes that require getting on my knees to access. In a perfect world I would make a copy cat kitchen of so many I see here. I would paint all my cabinets a light creamy color, put a marble look a like silestone (or the real stuff) on the perimeter and my walnut in the middle and every cabinet would be fitted with a pull out. And I would have a cleaning lady. As long as I'm dreaming. I'm afraid that I would face chipping on the paint with our busy kitchen. It just seems risky.

Everyone: I made a mistake, the cabs are alder, not maple. Similar though but with age the finish has yellowed a bit to make them kind of a light honey color.

Renovations are scary. We just did a minor one - counters, appliances, backsplash, sink, paint - and I was biting my nails as each piece went in, wondering if I'd made the wrong choice. I think it's normal to have doubts, especially if you're working with some elements you already own and don't get to start with a blank slate. So I think you should trust your instincts! Light perimeters with a walnut island and medium floors sounds lovely. If you like marble, Cambria has a colour called Torquay that is meant to look like marble, and there are plenty of other light options if that doesn't do it for you. I'd take a cabinet door and a sample of your walnut to a few showrooms and look at as much quartz as you can find. Good luck :O)