Love the idea of an atrium house, especially if the sun as high as it appears to be in your renderings. Here (60°N) maintaining the grass patch in the atrium would be quite a challenge...

..but I didn't feel like creating a half wall then try and insert it so that it shows and doesn't mess up the rest of the room, so let's just pretend that the backsplash on the wall above the sink stops at the base of the cabinets...

You probably know this, but a possible workaround for a backsplash up to base of cabinets is using a baseboard with tile texture on (sections of) the wall. ok