Subway tiles.

I'm going to become known as the decorator who hates backsplashes, but you seem to be getting along fine with out them. I would add about 4" of the same material as the countertop along the walls to finish the look and stop! Essentially you have a monotone kitchen except for the red thing at the window. I'd take down the red thing and focus on a way to add a little grey highlights to your cabinets, find some ceramic decorative items that have the floor color in them along if possible with grey and white and enjoy.

I think stainless steel pennytiles or similar look would look fantastic in your kitchen! Sort of updated retro look. Or, even a hexagon style. If the pennytiles doesn't float your boat, a stainless subway would look fab as well.

I would suggest undercabinet lighting.

I am having the same problem but my counter top is too busy for a lot of the different backsplashes, but I agree with the first comment of the subway tiles seen photos of gray countertop and subway tiles and it turns out real nice

My thoughts are a mosaic..Mix of glass and solids would look fabulous..I agree..Remove the red curtain topper..Not that I am opposed to the colour.It just seems a bit insignificant.
The attached image is called Venetian Platinum Mosaic tile..

Thanks for the ideas. Yes, the red curtain thing was from the previous homeowners and we haven't taken it down or decided what to do with all the red throughout the main floor. That's another project waiting to happen.

It looks amazing! Amazing how much difference a backsplash can make.

Love it....very nice....

Look what a mess she made

oh wow what a difference! Love it!

Looks great!

looks great, very modern