I do not like the look of the sidesplash here
Part of the problem with this installation is the contrast of light countertop and very dark walls.
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No sidesplash
Looks like countertop fits tight to the wall on sides. Contractor would use a clear silicone to seal the edges. Or a paintable caulk. If it's done well, you can get away with no backsplash.
Tile idea: You could tile a "frame" around the mirror instead of going all the way to ceiling.
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Maybe do corner shelves instead of cubby?
NOTE: Very thin horizontal line of deco tile
simple niche
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