A focal point in a room is any décor or furniture that grabs the viewers' attention the moment they walk in. This piece also anchors down the whole look and feel of the space, establishing the overall aesthetic. In the bathroom, there are several pieces that you can choose as the right focal point.
Do you have a window overlooking some gorgeous scenery? Instead of covering it up, accessorize the window with the right treatments that can allow the view to be the focal point of the room.
An antique bathroom vanity is another focal point that you can take advantage of. If you have a piece with rich dark woods, painting the walls in a neutral color will allow the vanity to pop out and catch everyone's attention. You can even dress it up with the right wall mirror and wall sconces.
In a powder room with little space, the sink itself can create impact - opt for a vessel sink with intricate detailing or a color that contrasts the rest of the decor in the room.