Personal preference - they both look great! But the black grout is more of a statement (which i love!)

The patterned ones come in a mixed box, as in a mixture of all patterns. You could have all patterns or throw in the plain one with slight marble effect (Hex Carrara Bianco) as in the attached photo from a Beaumont tile brochure. If your room is small you could consider the lighter version which is white and grey - Hex Blend Bianco.

Charcoal will give you more scope to mix in other items around the pool and is much more modern.

The funny thing is; if I verbally explain it to people they seem generally unsure or negative, but those same people, having seen in person say they're in love with it. Maybe its just people being conservative or scared to take risks? I am in the suburbs, but its an ensuite, and its EXTREMELY large for an ensuite (those black tiles are 600mm sqr.). I dont know if its "deco" - perhaps I dont understand what that style is (i thought 'deco' was 50s-60s style) - but I was shooting for a bathroom you might find in a high-class hotel. The master bedroom has it's own hallway - to give it the illusion that it is tucked away from the rest of the house. Clean lines, simple, luxurious. I'm trying very hard to "pull back" on it - keep the pallet simple, and try not to over-complicate it. I've kinda had to make it up in my head as I go along; there isn't much in the way of inspiration I could use to guide the way (at my budget). Even those flat, gloss black tiles were EXTREMELY difficult to source. But thanks so much for your comments guys and gals.