Oooo, I love your encaustic tile, beautiful. I love this look, one of my all time fav bathrooms below. I would probably go with the small tiles, but only personal preference. I would also match the wall grout colour to the wall tiles. How are planning on laying them? That might make a different in which one you choose. Both would look gorgeous though, you really can't go wrong with either option!!

What size are the tiles? 600x300?? I prefer brick bond. We used 600x300 concrete look around our pool and outdoor areas.

What colour fittings/fixtures do you intend to use? I'd love to see a photo of the latte chocolate tiles? But I think it sounds really nice :) Will you be doing a feature wall or keeping the latte colour on the floor and the white solely on the walls?

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.