With colors, flooring and furniture styles--it is best for the floor of an open floor plan, if you cannot stand in one spot and see three differences. For example, if you can stand in one spot and see 3 different floorings, your eye will be confused and it will stop the viewing flow of your home.
With color, in an open floor plan you should have one carry thru color and you can then mix in another new color with the carry thru color in another area.
With furniture styles, you should make a commitment to one style, and you can add in a piece or two of another syle that you like. For example, even a modern or contemporary styled room looks great with a large antique sideboard.