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!

I'm in tile retail and the most popular size for large areas domestically is 600x 600. The large sizes are gradually becoming more common but no where near the colour range of the smaller sizes. The only advantage of the larger size is less grout, but this wouldn't be much in a domestic size room. The most important thing to remember is how will they be cut in a room or a hallway. You don't want a giant tile then a 150mm slither down the hall. If you consider the larger tiles remember they are unforgiving if your floors are not that level. Laying costs may also be higher.

Ali, I think you are overthinking this, let your back garden be more natural as a contrast to the structured effect of the tiles in the house. I don't think you need consistency, the pool changes the whole vibe of the area so design for the pool to create a welcoming oasis - think tropical island resort. Have you checked with your local Council if there are limits of hardscape you can have? Some Councils do limit this and that will include your roof, driveway, paths, patios, the pool, etc. As well if you want this much hardscape you will need to consider runoff and drainage, particularly to ensure your neighbours don't get swamped in heavy rain or you have areas that puddle and take days to dry out. Consider summer heat too, sitting outside and the radiated heat that comes off hard surfaces, white and light colours reflect heat while dark colours absorb it. As well too much hardscape does not absorb noise - your neighbours will hear all your conversations and noise from the pool will be amplified. If you want that pool area to be inviting, then it needs lush greenery around it to offset this and soften and cool. Carrara marble tiles around a pool look fabulous and would be a great contrast to your dark tiles indoors. The area outside your kitchen should be grassed and include gardens as space for your dogs, even a small tree or two for the environment and to create shade for the dogs. Artificial turf gets extremely hot and would certainly not provide a pleasant or suitable outdoor space for them. I think I would read up on the breed of dog you plan to get also and fully ascertain their needs to ensure you provide properly for them. If you are planning children down the track, they will want a nice safe, green area to play too.

Hi Caroline, A few inspiration photos for you, try using subway tiles in a stacked style for a modern contemporary look, much more stylish than the overdone normal subway look, would look great in both areas, your tile store will advise the size of tile that will best suit your requirements.