With white fixtures, keep your floors and all tile white or a stone that is mostly white. You can paint the walls above the wainscot (which might be glossy painted wood or beadboard, or you might employ a cabinet for the sink that was painted a very soft sky blue. One narrow trim piece of tile running through the white tile might be the same tone of sky blue. Then, add blue linens / towels / etc. [houzz=] Now, consider what other colors are in your home and select one that is clear and soft and lovely with white. You might use that color instead of sky blue. I used sky blue because it is the color of water and therefore always appropriate in the bath, but you can make the bath flow with the colors you have or plan to have in your home. If this was a master bathroom instead of a common or guest bath, I would shift the choices of stone and tile from white plus white to a lovely off-white, cream, or almond tone - like travertine. Use a neutral like chocolate on the cabinet and add color only with linens and perhaps some art on the wall. [houzz=]

OSB board will do the trick. You need another photo for us to offer a species and finish. Natural finish (clear coat...water based polyurethane finish...NO oil modified) in a low gloss or satin finish on white oak with FLOOD LIGHTS will offer the same "look" as the poor photo. Beyond that, you will need a better photo.

Your choices don't flow well to me. The flooring in your photo is pretty (very dark...are you okay with it showing every footprint, smudge, and dust bunny? If so, that's fine). From all of your options there I would do white cabinets with the Himalaya White granite. But you said ignore the granite. :) I would go for the gray cabinets with white quartz everywhere in that case, but personally I'd worry about gray cabinets being very dated in a few years. Is there another quartz option that you could pair with the white cabinets that is light in color and maybe has some movement, like LG Bianco Drift?

I am assuming you haven't finalised your wall colours and colours of any other fixed elements. In case you have finalised your color scheme you would need to see which of these colours blend well or complement with that scheme. Assuming none of this info is available, then you could look at the neutrals which go with all colours. The white tile and the 2 colours at the end would be preferable. If you want color on the floor as well as drama, you can choose from the 2nd options from both sides or even the 1st from left.