The most cost effective way to update a room is changing the wall color. Otherwise this bathroom looks fine.

here's what I would do, paint the vanity a lighter color, and the chair to match, add a cushion to soften the look, replace the light over the tub, it is totally wrong for that space. Add a small chandelier instead. Also replace the outdated mirror with a nice decorative one. The paint color should complement whatever colors you choose for you master bedroom.

Also paint the baseboards a lighter color, and add crown moulding.

And if you are really handy, remove the light over the sink and instead put two wall sconces on either side if the new mirror.