We're rebuilding a house from the 30s.

The kitchen will have white cabinets with a wooden butcher counter (golden oak) and a white tiled backsplash.

To add some contrast we'd like cement tiles on the floor and I found a provider who has immense variety. They even have a simulator where you can make your own, choosing the pattern and the color that goes in each bit.

Problem is... I'm totally confused with so much choice. I know this is fairly personal, but does anyone want to jump in and help out?

Here's the simulator: http://www.ladrilho-hidraulico.com/Simulador/index.php

On the top left you just need to introduce the tile reference where it says "escolher padrão ref:" and then just add the colors and organize the tiles on the right where it says "crie o seu tapete virtual".
I'm inclined to greyish tones with a splash of either yellow or peacock blues and greens.