Beautiful kitchen! You already have a lot of white, and adding another runs the risk of it being just a bit off from one of the other whites. It would be really pretty to use a color like green or blue, or whatever your favorite color is.

Mockup:

Before you decide, do a search here and read all the posts about all-white kitchens with warm/cool backsplash challenges. It's hard to "read" whether any of these will work in your kitchen due to lighting, etc....so hard to decipher on a computer screen. If I were you, I'd go with a soft color, or even a frosted gray as it seems like you like that tone.