As a kitchen and bath designer, I do not think it is too busy. Since both tiles will be white, it will just add a little something special to the space! I would make sure whatever liner you choose to frame the herringbone is simple and not too chunky, so that it doesn't take away from the simplicity of the design. Your kitchen looks lovely by the way! I look forward to seeing the final product!

Thank you so much! I purchased quarter round to go around it.

Love it!

Since subway tile is one of the most basic tiles you can use for a backsplash, I think the herringbone will add a nice touch.