What are the lights meant to highlight? If, say, bottles on the top rack, then I'd move the sconces up. But they risk being a lot of glare in your eyes.

Change to brown or "nickel" outlets so that they disappear. The dark brown actually draws the eye, and outlets and covers come in many shades. See these on brown glass tile, for example.

Copper might work on your wall.

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Thanks, acm. I had a friend suggest getting paintable outlet covers and trying to match the grout. The lights are not meant to illuminate the bottles. I did think of that: the higher sconces causing too much glare.

I think they are perfectly placed. You might try to find bulbs that don't hang any lower than the shades, that way you don't get the glare that you get from the bare bulb showing under the edge of the shade.

If you move the outlets, it will take away from that cluttered feeling. It only feels that way because they are contrasting the wall. You might want to try moving them to the outside of the buffet. Like in this picture below. It will still be convenient for when you do use them and they can easily blend in.

GFCI Outlet done by our Santa Clarita Electricians