What a great job you did. So good that you just went with white. The concrete floor tile on wall behind the vanity would have been too busy after now having seen the finished product.

It's the floor colour that's the main problem, neither one thing nor the other, and certainly wrong with the benchtop. Leave the wall tiles if you like that sort of thing and find a way of covering the floor probably with laminate planks on an underlay. We have a European Birch golden coloured timber floor but softer grey splashback and it looks fine. It's not an award winner but the floor and cabinet carcases had been there twenty years and it was affordable. Don't even think about painting the floor or putting down mats but a clear plastic runner in front of the sink works well for us.

because the water could seep through the joints between the new tiles and sit between the two layers and affect the seal and also raise the height of the floor and affect the slope to the waste outlets..but, why do you want to retile if you're not using the bathroom??...for immediate resale consider bathroom wall to wall bathroom carpet, new wall paint, new vanity, taps and light fittings which should also be cheaper than tiling over the top and, if it's not allowed by the body corporate, it will be a risk to future sales as it should not satisfy a proper building inspection

Nup, a good tiling job requires a good substrate. The best tiler in the world can't make a bad substrate look clean and good. No point on spending money on new tiles and a good tiler over an inferior base. Rip it all down, start again and get it right before tiling. Best of luck, Dr Retro Of Dr Retro House Calls