Protect your wall tiles with cardboard and take a hammer to the row of counter top tiles that are against the wall. Break them up good. Wearing gloves and using putty knives and screwdrives pull out all the little pieces of tile from that row closest to the wall. Wiggle them out from under the backsplash tile, they should come out fairly easily. This clears a distance the thickness of the tile for the counter to pivot up upon removal before it contacts and loads your backsplash tiles. If that proves to not be enough set the depth right on a circular saw or rotozip and zip through the cement board and pry that off too. It will take more finesse then normally is used when demoing kitchens but with a little caution, it should be very doable.

Yes, subway tiles have been done so much…why? because they are a default. Large, small, white, stainless, glass, the subway tile will continue into the next century, along with the hex and black dot. The ultimate “little black dress” for a bath or kitchen. (Boston knows its subway tile.) Fish scale…great, as well. Kind of beachy or maybe a nod to art deco. Watch out though for the color of the grout you use. It is more noticeable with fish scale than with subway.

go w/your herringbone design. it will be fine. choose the thinner, longer tile like a 2x8, 3x9, 2x10 size. like this size. Cle basica farmhouse tile you could do a layout like this. a vertical stack, offset: The smaller mosaics will be too much. you already have the floor. pick something a bit larger for the wall. Although, this super smaller herringbone w/the matching white grout could work. It's Bedrosians this is a 2x8 chevron. these are big enough. Tilebar, Nabi harlequin chevron in 3 diff finishes of white marble Cloe tile

Hope this project ended well for you! I also have Calcutta Arno counters, white cabinets, and am in the same dilemma with the white backspash tiles. I like 3x12 subway and picket tiles but the ones I pick are too stark with the warm white counters. Would love to know what you decided on and how you like it.