IMO use the same material you used for the raised bar backsplash and no gray grout with white tile in a tiny kitchen I would just leave behind the stove or get a stainle sheet for there since it looks like you have quartz counters and I would do the backspalsh the same height as the step up on the bar

No backsplash. Leave it as is. You’re adding focus somewhere that doesn’t need it, and creating problems for yourself.

Can you take a picture without all the kitchen items on your countertop? I can't tell if there's a shadow or if you have a b/s on your wall already.

I agree with Rachel Lee. When I studied this, the first thought that came to me was, "Why do anything? There is nothing wrong with it."

Leave as is.

You already have a stone backsplash. You don’t need to add to that.

You already have a backsplash. You don't put a backsplash on top of a stone backsplash.

I can't tell, do have something going up the wall above your counter already?

In any event, the only place one really needs a backsplash is behind the cooktop and behind the sink.

Do you already have a backsplash behind the sink?

If not, you can use the same material you used for your counter.

The area behind your range is so small, why not think about stainless tiles?

They come in different patterns and are very attractive and easily wipe clean.

They even come as peel and stick from Home Depot.