Sorry-- I just saw this post. Take your aggressions out with a hammer. I think you'll find the tile comes up pretty easily, especially if this is directly over a single layer of plywood. In fact, I'd like to know how it's stayed down for ANY length of time if it's a single layer. The thing that may be tough will be the thinset. But I've got plenty of ideas for that, as well. Take the tile up first, though, and once the tile's up, we'll have a better idea of what's going on underneath, and I can better advise you on how to proceed. Four cautions, though. First remove any breakable objects from the area. Second, wear safety glasses. Third wear a long sleeve shirt. Preferrably a heavy one, like flannel or chamois. And lastly, wear gloves. The reason for these precautions are that when you start smashing the tile, pieces are going to go flying. I've been known in the past to not worry about the longsleeve shirt part, and end up needing a stitch or two (well, I SHOULD have gotten em). (thin pieces of duct tape make great butterflies!) :-)

I've read on this site that some (all?) extremely large format rectangular tiles tend to have some bowing to them due to the size and what happens during manufacturing. I believe Avanti (the pro above) is suggesting that you simply cannot avoid the lippage / visible bowing when doing a 1/2 stagger like your picture.

beautiful kitchen. and yes, I agree. plain white subway is so overdone. would you say the gray in the countertop is more cool or a warmer gray? it's hard to tell because of the yellowish cast from your lighting. here are a few examples of some tiles that you could use. see if you like any of them in this comment, or the 2nd comment: Lunada Bayabove, ceramic water colors saw this at my tile store. Emser is the brand. it's a warmer gray, but they have other colors. encore ceramics in Silver Crackle elongated hex or Picket design. many colors 6th ave, Walker Zanger glass tiles. if you stay w/a solid, it will work. this is a muted, hand-made type of linear glass tile in a frosted iridescent finish. You could go w/grays or whites, but consider very soft blues or sage/greens too. you could look at some marble options, but pick a larger size rather than a small mosaic. go to Tilebar and look around. they have a ton of selections. you get 5 samples for $5.

Lovely tiles! I like that they cover the back wall. The sink looks great too! Here are some guidelines to think about for a wallpaper: Your tiles are a small scale. So pick a wallpaper that has a medium or large pattern to contrast with the tiles. I would stay away from geometrics, again for contrast. Something with a flowing, natural feel would work well - think florals, branches, or grasses. If your bathroom is headed in a more modern direction, something with abstract swirls possibly. In order to let the tiles stand out, use a wallpaper that’s tonal - as in subtle color variation and very low contrast. You have a lot of leeway in what color you select. Personally, I would use something in varying neutral shades, like cream to taupe. But you could us a paper with a subtle pattern in shades of greens, blues, or reds. Maybe dark grays or near black if you want to get dramatic. Hope that helps! Best of luck.