Hello again, Definitely not too warm. I am not entirely sure what paint colour you are thinking of but as pointed out - easier to adjust paint rather than the other way around. If the tiles were really grey and the walls were that tone as well, it would be a very flat, souless look - the slight touch of warmth in the tiles is a good thing and honestly being so neutral your options are huge with colour of walls, particularly if you are intending to use this tile throughout. May I suggest you choose a paint colour and then use different depths of the same colour depending on sunlight, dark corners, more impact in certain areas etc to create the interest. Be wary when you have such a neutral, albeit very tasteful tile, it may be wise to adjust the paint in this way to lift the level of interest. Take a look at the following colours - Resene House White and Resene Concrete as starters - very unobtrusive. You could always go for a hit of charcoal in areas too. Avoid any "feature" walls - do the whole room - nothing wrong with strong, dark colour, even in small rooms - think powder room or laundry if you are not brave enough to do an entire, larger room. I am also assuming you will be introducing plenty of white trim on skirting boards etc - for what it is worth, my go to white is nearly always Resene Alabaster. Loving the sound of the carrara - such a classic. Hope that helps :)

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.

Have you priced having the whole lot re waterproofed and tiled? You are already doing the hardest section, it may not be that much more to do the lot. Otherwise agree with above match to the white tiles in the rest of the bathroom. But it will always look like a repair.

Personally, I don't think a 3.6 x 2m is small at all so I think the tiles would look good. Our bathroom is a bit smaller than that (but way larger than our old bathroom), 1.8 x 3.4m, and we are planning to get white 30 x 60 wall tiles and 60 x 60 floor tiles. I had not even thought it would look small based on those tile lengths and the tile place had a display bathroom with one wall (2m) in the these sized wall tiles and I thought it looked great. They also had the 30 x 90 wall tiles (longer length but same tile, which we saw laid in the 2m display area as that ) but those were a bit more cost wise so I think for our budget we have to stick to 30 x 60... But I do love the longer tiles (and wonder as it is not the standard size, if it will be less likely to date as quickly which could be another positive!) so I agree to do what you like and don't worry as someone will always disagree or recommend another way based on their persnal preference.