Design aside, I'd hate to have to clean the kitchen dirt off the wall paint and end up with rough patches and stains, so I'm pro-backsplash))) I love your windows, I think you can accentuate them by adding the backsplash all around. In this case, it will not look like there's too little of it and it would encase your windows beautifully. You may consider adding arches above the windows to connect the top cabinet for a more cohesive look. Cheers!
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backsplash
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