Cream goes with anything except white/beige/etc.
For a light/airy/classic feel go with a cool pastel (Tiffany blue, lavender, light grey, bottle glass green)
For an earthy/solid feel go deep (slate green, dark grey, grey blue, cocos browb, dark red, plum)
For a vibrant feel go 'pop!' (Peacock, red red, chocolate brown, wallpaper in gold &/or silver)
For a rustic or desert feel go warm (mustard or mauve)
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Flooring depends on paint, or vice versa
Tiny tile is classic (think 1900-1940) and goes with anything EXCEPT earthy (but does go with red)
Black and white tile ditto (but I wouldn't pair with red)
Slate is earthy, and pairs with airy or earthy (there's a metallic blue slate that goes GORGEOUSLY with cool pastel/earthy/or vibrant colors. Peacock blue & Tiffany blue, especially.) I'd go with small and large tiles in pattern.
River rock is texturally interesting, but hard on bare feet.
Wood pairs with anything, but match tones carefully. Teak or bamboo is best for bathrooms.
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Strong 2nd for looking at bathrooms in pottery barn, restoration hardware, bathroom edition of This Old House, etc. several paint companies let you take picks of a room, upload, and try out different paint colors.