You have a lot going on texture-wise so I'd probably keep it simple in terms of rug texture or there'll be too much going on at once. Warm would do well in this room though, so that's good! You mention it's away from the light outdoor area, is this photo an accurate representation of the lighting you normally get in this room? So in summary, you might want to have a look at rugs that don't have much texture, and are a bit brighter in colour to help brighten up the room. Below are just a couple of examples of rugs that could work, and one more neutral example.

Hi Sue, I think it would look amazing if you used some tiles with a bit of texture. The wood look tiles that are popular at the moment would be an example. If you chose a colour that toned in with your floor you would get a really nice cohesive look but with a bit of interest. I've attached a photo of a recent design of mine as an example. Just a suggestion!

there is also a difference between ceramic and porcelain tiles - often these issues come down to a combination of (a) tile batch size/consistency (b) tiler's skill/capacity (c) communication in that if the tiler opens the tile box and he can't practically achieve what he thought he might because of the general discrepancies in size then they should at least speak to you before they start. So often with many issues in this game, it's about managing people's expectations and having open/honest discussions at the right time. When this breaks down, problems and disappointment is more likely to occur......so coming back to it, if you have high quality porcelain tiles that are millimetre perfect, square and flat then the capacity to lay them with minimal spacing is higher. Also the substrate/prep plays a part as if it's all out of whack and not perfectly straight/plumb/square then you'll be in all sorts trying to achieve the minimal tolerance detail.

I think she may have been referring to what is called a "French Pattern" which looks like a random mixture of square and rectangle tiles, often in travertine. However while it looks random it is actually carefully planned, and the tiles are made to a consistent thickness. It also depends on the type of tile that you are using. Many traditionally hand-made ceramic tiles have a natural variation, which adds to their appeal and visual interest. Other types of tiles, such as your porcelains are much squarer, flatter and almost identical. I would suggest that you go with your your choice of grid pattern, as laying a random pattern has too many risks (plus your tiler will hate you and charge lots extra). Be very careful about the selection of your tiles depending on your preference for a rustic more organic look, or a hard-edged architectural look. Make sure that the surface that you are tiling to has been properly prepared and is flat, smooth and true, as your tiler will not be able to correct imperfections if you have a bad wall. Best of luck, Dr Retro of Dr Retro House Calls