Have you looked at marble look alike tiles? Some look very much like the real deal, others look kind of crappy.

I have looked at some of the porcelain marbles and thought that they just did not have enough detail, or I worried that they only had a few patterns that would be repeated on my walls and my eyes would see them (I unconsciously seek out patterns to match). I recently found this one, though, and I am wondering if it might work. Of course, seeing it in person is the only way to tell, and the depth of the glaze work is going to determine if it can at all pass for marble, or if it looks like marble-like paint. It does pass the test of not only having a few patterns, though!

http://www.qualityflooring4less.com/anatolia-classic-carrara-porcelain-tile-12-x-12.html

Download the Anatolia Classic Brochure under the "Manufacturer Details" section and you will see a large quantity of the 12 x 12 tiles and how much variety there is in the pattern. It is rare to get a manufacturer to show this! Too bad they have a 300sq ft minimum flooring order. I don't know how that applies to this wall tile...

I am putting a solid surface in my shower itself and this tile on the room walls. The shower will likely be Swanstone Ice or Tundra from the Altitude Series. https://www.swanstone.com/flipbooks/Swan_Altitude_Brochure.pdf

OP: I went through the same exact decision (even down the the fact that I also have a 1920s home). I went with standard white 3"x6" subway tile (50% offset) on the shower stall walls, and 1" white hex (gray grout) on shower floor and room floor. The colorful tile in a PP is a 1920s look, but the sanitary all white was, too. My neighbor's 1920s home - never renovated at all - has white subway tile in both full bathrooms (half bath is all pink - tile, fixtures, etc.).

I have an orginal main bath in my house still it has beehive and subway tile the problem I had with my new bath, which is an addition, is no subway and hex tiles made today compare with the beautiful crackle subway in my main bath. And the hex is different too. Todays cove pieces and caps fell flat. Here is my orginal 1920s shower tile and fittings.

Here in Detroit, the subway tiles were mostly used in the basement laundry or secondary basement kitchen areas or other areas where servants worked. Our 1920s and 1930s bathrooms were done in beautiful 6 x 6 tiles in pottery-style glazes. These are the kind of glazes where there is variation tile-to-tile, so that there is a feeling of texture to the walls. The walls were usually tiled to the ceilings in the kitchens and in most of the bathrooms. Very pale yellow, peach, greens, blues, some tans are found. I believe that our long period of low housing values was a savior to our Detroit ceramic tile in older homes. No one would remodel a house that was not worth much, so we still have house after house with original tile and plumbing. We have an art pottery works called Pewabic here and some sun rooms have floors and fountains done in their distinctive darker Craftsman colors.

There is a series of websites for each big city in the US called "Curbed [city name]" and Curbed Detroit shows these old homes and mini mansions and real mansions when they come up for sale. If you like old homes, check and see if you have a "Curbed" site for your city and subscribe. I have learned so much about old houses and the renewal of Detroit reading that website.

roarah, have you looked at American Restoration Tile in Little Rock, Arkansas for old-fashioned looking tile? They say that theirs is identical to tile of your house's era. They will even do a crackle glaze in the same manner as was done then.

http://restorationtile.com/index.html

Nancy, thank you for the link, I love their floors but their wall subway tiles literally fall flat compared to my originals so I chose a different route altogether but will use them if I need to redo my orginal floor in the main bath. My wall 's orginal tiles protrude over an inch off the wall and the top piece is more like a full subway with a cove while restoration tiles all have skinny pencil like caps nothing like the real thing . The bottom cove pieces are different too :( .

Look at Atlas Concorde. They have nice porcelain substitutes that look super close to the real thing. My shower is a mixture of it and some real marble and to be honest the porcelain is prettier. Also, the pricing is moderate.

https://www.reminetwork.com/articles/digital-fever/

If you read that article on digital inkjet printing for porcelain and ceramic tile you'll see that repeats are a thing of the past for some manufacturers. 30 12x12 tiles before a repeat with just the standard memory.

http://walkerzanger.com/collections/products.php?view=mat&mat=new&coll=Calacatta%20Porcelain Here's a link for Calacatta Carrara is available and limestone from other sources.

" Italian tile technology replicates with amazing fidelity the varied veining of the actual marble and the smooth but slightly undulated surface has the hand feel of true stone. Offered in multiple sizes, Calacatta Porcelain allows you to bring the beauty of Italian white marble to any space."

We had the same dilemma. We loved the look of white marble. We were going for a timeless look but we didn't want the maintenance or water discoloration especially in the shower or floor. I also didn't want a lot of grout lines. I really wanted to use a solid slab but it's very expensive. The other option I considered are these beautiful large slabs of tile but it wasn't any cheaper. We ended up going with a 12x36 high quality Italian ceramic tile that looks just like the very expensive Italian statuario marble. I picked out a slab of very white Italian Carrara with some veining for the custom countertops, built in shelves, window sill, and threshold. I used a 12x12 honed/mat tile on the floor because it's less slippery. All the other tile and marble were polished looking tiles. As far as far as not using the same tile twice..I think each box had 12 different patterns. I laid them out first, and flipped some over so they looked completely different. The marble and tile all matched very nicely.

Villa Lagoon has beautiful cement tiles with a Cuban/Mediterranean/European vibe that could work well. In fact, they have a "South Beach" collection. https://www.villalagoontile.com/cement-tile-in-stock.html