Have you thought about stainless steel backsplash tiles? https://www.houzz.com/products/4x11-honeycomb-matted-metal-peel-and-stick-backsplash-tile-set-of-3-brushed-st-prvw-vr~100903589. These tiles would look great with your stainless steel appliances.

OK, I don't like the tile I posted and wish I'd been more precise. You're not going to go wrong with white subway, but if you wanted permission to walk a little bit on the wilder side, I think your kitchen could pull it off. What I was trying to suggest was a shape idea, like this perhaps. I disagree about using a traditionally laid herringbone accent, especially with a thick border. I would think it was too stodgy if this were my little kitchen, (except maybe the sideways pattern in eam's first two examples.) If you want an accent and use subway, you could also consider a stack or a chevron pattern. Here they use that pattern for the whole backsplash. Or do the BS in matte tile and the accent tile in a gloss finish. Or lean a large, funky handmade ceramic plate behind your range and support a starving artist. Your kitchen is darling. You didn't ask but I'd paint the stools. I'm just full of good ideas for your time and money, aren't I?

I don't know what your client has in mind completely. It might be worth asking the client for some inspiration pictures for what she has in mind. I think some glass mosaics might be overpowering for that granite. But there are some glass mosaics that might work as long as they are very plain. Super white glass tile Maybe something like this with a tiny bit of pattern: Silver planks glass tile Or maybe this one which might work with the colour in the counter: glass mosaic - raw silk

he's 83. he's a builder, not a designer. I have large plank hardwoods. I actually did a herringbone inlay w/zellige tiles. I'm sure his head would have exploded I was going to do this design on my backsplash but I didn't have enough of this tile (it was a clearance buy) and since I have black appliances, it would have been too dark. But for him to say this classic design would clash w/your floor,,,,huh? what kind of floor does he think you need to have? what you picked will basically look like this, shown here w/wood floors: Do any of these pics clash to you? of course not. tell your builder to build, but keep quiet when it comes to tile so, how exactly does the floor clash? to me, a plain old subway layout is so trite, and so completely overdone, I can't take it anymore. if you have a country farmhouse, great. your kitchen is more transitional than traditional This is a bit more traditional look. the beveled arabesque this is how your tile will look with more of a gray grout. the first pic I posted will be the look if you go w/a white grout. you can barely see the design