I think your white tiles are fine and I like the size. It will look good. Here is a similar tile we used in a kitchen from Walker Zanger that has a bit of undulation to it (no color change) and we paired an arabesque from the same tile line for over the range. I think this is similar to the look you asked about, except you wanted to do a herringbone over the cooktop. Sounds like it would work, but you would need to match up a smaller tile for that (same color) unless you have a really large space over the cooktop. A long tile would not create much of a herringbone pattern in a small space. Love the countertops. Good luck.
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Faucet?
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