Nic's,,the 4" piece should come off easy enough. you may tear the paper on the backsplash, which is ok if it's not too deep into the drywall. I guess if you were on scene you could have asked them not to install it. I mean, what difference is it to them whether or not it goes on the wall? to say it would be more money not to have one, is ridiculous. it takes more time to cut one and finish the edges! but, whatever. as for the design, it's a herringbone. and those I've shown you come on 12" sheets so you don't have to do the actual design (which is very difficult) the first one is calacatta marble in a 1x2 herringbone (also comes in a 1x4, which I like better). You can find this all over,,,even Houzz carries it. If you want the marble, then stick w/the Calacatta not the Carrara. carrara is a blue/white and will clash w/your counters. calacatta has a warmer tone to the stone. the 2nd on is a tumbled travertine which you can get here: https://www.pebbletileshop.com/products/Cream-Herringbone-Stone-Mosaic-Tile.html#.WhX_BLaZNT4 this will give you an idea of what it looks like installed (you can turn it longways as well) If you search "herringbone mosaic tile" you should get lots of ideas and places to buy them. this one is from Lowes, allen and roth. you could buy one and bring it home to see how it looks this is the basketweave this would also work. crackle glass by Merola tile. Olean Glass mosaic. I think Home Depot carries thesenothing wrong w/doing a little color. pale green, blue or gray would also work well. https://www.homedepot.com/p/Merola-Tile-Chester-Sage-3-in-x-12-in-Ceramic-Wall-Tile-1-sq-ft-pack-WNU32CSG/300341310 these would also look nice,,,they have them in different shades https://www.mercurymosaics.com/shapes/field-subway-tile/

I would paint the crown white, else the crown color will not flow, if you go from white to off white.

Thank you very much for the advice. I like Fantasy Brown a lot. I am not sure if it would work in my counter with the seam at the corner. It seems like pieces of Oyster White or Lennon are easier to join together discretely. Also, with the small appliances on the counter - microwave, toaster, coffee maker and kettle - I am not sure how much granite flow I will be able to see at a time. Is Oyster White look too simple in your opinion? What backsplash do you suggest to make it more visually interesting? What color of the floor tile is the best? My kitchen opens to the hallway/living room with red oak floor. I prefer not to have hardwood in the kitchen.

I would continue with the same trim/door color. My suggestion for walls with white cabinets, would be to paint them the same off white as the trim. Not the best example, but close... Add a runner that works with white/off-white theme in the room.