You should go to SW, or another paint store, and pick up a few swatches. Take them home and hold them up to your counters and cabinets. Fold them if necessary so your eye can only see the colors you're considering. Try it in sunlight, shade and with lighting. If you think you like a color, you can purchase a $6 sample from Sherwin Williams. Use a simple foam brush and paint the color on a quarter piece of foam board (WalMart has them, as would an office supply store). Then you can hold it up and see how it looks next to everything on a larger scale. I think the Kilm Beige is so neutral that it would work with the counters and pick up that light color in the travertine. It's hard to tell about the cabinets. You want to try them next to each other. Colors are affected by their surroundings -- you don't want the color of your cabinets to make the paint look too yellow or too pink. The only way to tell is to play with it.

i Would do the walls in a very light blue gray..take the blue in the backsplash tiles and find it 2 shades lighter almost a cool toned white....SW Ice Cube or SW Rhinstone might be close....

You need to make that decision in your room with your light. What we see on our computer monitors may not look anything like what you see in real life. In fact the floor looks like a different color in your two photos, which should prove to you that it's impossible for anyone to pick the color for you long-distance on a website. What you could do is paint the walls the same white color as the trim. Also, are you painting before you install the new floor? Painting should come last.

First change all the bulbs to LED 4000K that will help you choose the right wall color that will not change at night. Do you love all the trim ? I like the FP surround trim but IMO the rest is not worth high lighting so I would do it in the same color as the walls but in semigloss . I love the house and the floors the stone on the FP not so much IMO you have huge space so why is the TV in the corner. I am not sure about the size of that room but if you post that then maybe we can show you how to have 2 seating spaces in a big space one for TV and one for the FP A floor plan of the whole house would be great.