Unless you want to go pastels, I would keep the yellow shower curtain. I would remove the towel bar on the lone wall. I would put the towel rack on that wall, a little lower than you have it now. In place of the towel rack over the toilet I would put two framed prints, the frames picking up the color of the wood tones of your sink cabinet. The prints could be florals, landscapes, even modern art but should have the yellow and pink tones you want. They should measure about 20x20 each and place one over the other. The sink in on the far right therefore anyone washing her hands should be able to dry them there - place a hand towel holder on the wall next to the sink to the right of the mirror. Place a tall plant ficus/palm, or so, on the left side of the sink to break the mirror from the pictures. The planter can be in yellow of your shower curtain, or pink or combo. Hope you like my suggestios.

Linen curtains in a color close to the wall color are always a safe choice. Any art you love will always work. Just pay attention to scale and don't hang it too high. I would remove those dinky lamps on the desk along with the vase of sticks at the side. They really don't add anything but clutter to the space.

They appear to be magazine holders! I suggest, if you choose to keep them, that you put photographs on them, or art work, stacked in front of each other. Or remove the shelves completely. And replace them with art. Nothing on the mantle. And, if possible, get rid of the wiring. Bury it, or get a wireless system.

Unless you buy a complete set of something… you will be mixing wood tones. Some woods have grey, yellow, red,green…etc tones. I would try to stay within the same tone. We’ve mixed a few things by pulling a color out of another piece. We mixed these two… first pic is tv cabinet and other is our coffee table. You can also use decorative wood trays and objects to bring the other colors to each of the opposing pieces.