We encountered something similiar with about a 2" on the end of one wall, however we were going with the tile vertical and stacked above one another. We had a professional, who laid our tile in the majority of our house come over to answer a question we had about the window in the shower and before Hubs could even ask him about that, he looked at Hubs layout and said, "you never have that small of tile on the end of a wall." That and the issue of the window had us re evaluating everything. He wanted us to bricklay the tile (12x24, like yours with 1/8 grout line), as he said that was the way to solve any issues. That wasn't the look I wanted so we started over and Hubs, with the help of some people on here, finally came up with a solution. We ended up going horizontal but matching grout lines. Before any tile is laid though, make sure your tile is actually 12x24. Ours was actually a little less than 12 and a little less than 24. That little bit adds up when you only want 1/8" grout line and you are dealing with a small bit on the end of a wall. I didn't want bricklay pattern as I wanted a flow from the floor to the shower since we are having a 39" glass panel and 30" glass door. So far, it has taken hubs a couple of weeks to cut and lay the tile himself, but all the grout lines are even and we are down to finishing the bullnose and the floor. If you are wanting the bricklay pattern, then your tile guy's solution might work. Try drawing it out on the computer and see what it looks like. That's what Hubs did and it helped me see what he was wanting to do, or draw it out on the shower wall itself.

I'd want to do the same type of layout. But I'm kind of rigid like that in my thinking. It might look too close in layout, that the other looks like it was put in by mistake. So the limiting factor is the large format tile, recommended not to do a 50% offset. So I'd do the same with the wall, unless you really deviated from the pattern and did something totally different, like a stacked or herringbone. Again that is my take on it. Maybe others have other ideas and images of examples.

Plenty of rugs won't save you. I was giving the lab a bath. He bolted out the bathroom door after the bath and I rushed to close the door because it was drafty. He scrambled the rugs on the way out, I slipped and fell into the door jamb and broke my wrist. Would not use the tiles that are linked on a floor. They have R9 Slip Resistance rating which is the least slip resistant rating.

Do you have a box of the tiles? You could lay some on the floor and just see what is visually appealing to you. We did this, and decided to lay them left to right (not door to wall) because it is was just more comfortable to look at. If you lay out a couple of rows of tile one way, and then the other way, you will have your answer. When you do it, cup your hands around you eyes (like race horse blinders), so that you are not distracted by the rest of the blank room. Look at it one way, then switch it and look at it the other way. Whichever way looks better to you is the way to go. And just for the record, I like having a toilet room too. People have strong opinions on that subject.