I have gone your route weeks ago and made the round of finding a nice fake marble tile . You can look at my threads if you are still considering a fake marble tile . There were many options suggested by a lot of members on this web . If not than I think with your white walls and cabinets the only solid color that you can have on the floor is grey . I personally didn't like grey and went with the real marble . There will always be a difference between the real and the fake . You can see the difference on my threads too with the choices that I had and the real marble end result. Good luck.

With the tiles you have picked, I think a nice simple Porcelanosa floor tile in gray would look perfect. I haven't looked at much of their tile, but something quiet without much movement would be best. Let the marble and wall tile be the star players, the floor is supporting cast.

http://www.homedepot.com/p/t/202038615?productId=202038615&storeId=10051&langId=-1&catalogId=10053&MERCH=REC-_-product-2-_-202038613-_-202038615-_-N#.UZQkESufGDo

I think a dark floor would look best with that tile and the Carrara counter. Either a dark grey, large tile, or maybe tile that looks like wood planks in a dark brown.

I decided to use Moving Steel with this tile. http://www.irisceramica.com/modern/moving/steel