Just to offer a different view point. Your floor tiles look amazing. Why not flow the idea through and use tiles of that ilk as your splashblack. We have just recently finished a kitchen with a similar feel and our client opted for patterned wall tiles as their splashback. Based on your comment about the floor being chosen to banish boredom If you are worried about carrying through more of the same tones and want to inject colour, you could always do this through your accessories, that way if you fancy a change.... The colour tones you have chosen provide a great canvas on which to complement or have fun with colour.

I never, or should I say my husband, hasn't, got round to finish tiling behind the wash basin so we used a 'washable wallpaper' and it drives me mad everyday. It never ceases to surprise me how much toothpaste, soap etc gets splashed against the wall and no matter how much I wipe it, it always leaves little marks which are impossible to get off without damaging the surface. If I could, I would tile every last inch of the bathroom. A quick spray and wipe and it always looks clean. I feel like I'm doing an indepth scrub constantly and it still never looks quite as pristine as I would like

I would replace the dark worktop for a white one, if you need a refreshing look as no light bounces on dark worktops, hence why yours looks so cramped. then you add a white splashback too, subway white tiles are the cheapest of tiles and glossy ones bounce off the light great, which creates a more airy kitchen.. If you go for mirror splashback, unless you have OCD and enjoy cleaning 3 times a day, then forget it. it will always look smudged.

I’d do differently. I’d tile up to the top of the units making a straight line, that way would feel nice to the eye, with a good flow feeling. To add to the look, the shelf will have a lovely background when you are setting your plants, herbs or spices… . I’d actually install tiles in a light colour with mate finish.