Tile splash is ALWAYS best with counter top riser removed What is open gap space next to fridge? No green blue ANYTHING tile here please. Should have considered that preference before a gray tan mottle counter top was installed.

A simple white arabesque..... a very pale gray. Matching grout. Or a simple subway, same thing.

Tile does not really go well when you have that short backsplash. She should either continue the granite as the entire backsplash, or remove the granite and replace it with tile.

As far as color goes, I'm not loving the yellow/orange tones in the oak with the gray/black granite--you have cool and warm colors fighting with each other. Since she just replaced the countertops, I suggest that she paint the cabinets in a cool white color. Then select a color from the granite for the tile backsplash, or a white tile that blends with the cabinets.

I'd also replace the hardware on the cabinets.

I'd stay with the short backsplash she has and get another piece for behind the range, or put a piece of stainless steel behind the range. The taller granite backsplash finishes well under the ledge on the right. I'd leave it well enough alone.

The time to have made a tile decision is when the granite counter was fabricated. Now you are wasting material and labor to remove the granite backsplash and install tile, just because the current conventional wisdom is that tile backsplashes are the greatest and a short matching backsplash in countertop material is the worst. There's nothing wrong with either.

Thanks everyone- I agree that the lip on the backsplash should come off! I’ll suggest that to her. I like the idea of a neutral, cool tone tile behind then.

the opening by the fridge was a Tracy compactor, which will now be custom cabinet.

She has warm wood cabinets - so do I, so not a problem, but cool grays and warm wood tones do nothing for each other. If her cabinets are maple, a very soft, light silver gray can work. Too dark and the gray will make the maple look really yellow and the kitchen too dark.

Also, wood cabinets look best with a simple backsplash. Take the lightest warm color from the countertop (probably a cream or white) and try some samples with the arabesque and plain subway. Sometimes what we like does not work with what we have.

I tried white and cream - I found the white was too stark against my cabinets but my wood tone is not quite the same. When the tile has been installed, but before it has been grouted, there will be the illusion of a contrasting grout. She can decide then if it is too busy a look or works.

If she has not replaced the microwave yet, tell her to consider a dedicated stainless vent hood and get a small microwave and place it elsewhere.

My kitchen:

https://www.houzz.com/photos/my-pics-work-in-progress-phvw-vp~109854040