As it is west facing, I imagine you get lots of beautiful daylight? The downside of dark counter tops is that they actually show lint & dust a lot more than a lighter worktop. I would advise getting a dark piece of plastic or tile & leaving it in your brightest part of the room for a week & see how much you have you polish it up to get an idea of if it will be practical for you. The upside of lots of daylight is that you can still go for warm undertones & they won't age looking yellow as they get older, I would be tempted to do a warm grey base & lighter top in your space, a tip that we don't do in the UK enough is boxing in the space above the wall units, by doing that it will make your ceiling look higher & the space feel bigger, some MDF & a splash of paint will give you the look for minimal cost, you could even or handles in some of the space to give the illusion of custom cupboards are there. Finally I would do a porch light & be brave with brass finishes. A west facing room is such a treat I would be tempted to give it some wow factor in the finishes to make it feel like a retreat.

I know it sounds funny but a pale green grey would works well with the cream as it could bring the tone of cream down to make it feel more white. Here are some examples for you to see It would still depend on the tone of your grey wall tiles as if they are a more blue grey i agree with Rukmini Patel Interior Design that a blue would work well too. Here are some Farrow and Ball colours that could work and you can get sample pots off to test. Which you can then colour match to a dulux or a valspar paint

I would definitely go white! You've got great texture and color already with the elements you have listed for the room. Let the white be a striking backdrop for the stars of the show. From the picture you posted the cabinets look like a white-ish color. So having a bright white wall will show off the lovely grey tone of the cabinet with some much needed contrast. I recommend Sherwin Williams High Reflective White, SW7757. It is the truest of white with no tint of green, yellow or pink. Just an impressive white. :) I wish you success on your fun project!

Having just completed opening up our kitchen and room beyond we have gone through the same process of finding colours which suit mixed use space. We looked at a lot of blues and greys, even a flirt with reds, but came to the conclusion that they looked old hat. Final decision was F&B Babouche for sitting area (a glorious rich yellow), and again above the cabinets to link in with the kitchen. Kitchen cabinets Lulworth Blue lower cabinets, Wimbourne White higher ones. We are delighted with the result. it looks fresh and vibrant after all the dull grey years. Great thing about paint is that it can easily be changed in time to come! just go for it and enjoy!!