My first thought is that the striped wallpaper is a faulty attempt at gaining visual height under the lovely stairs. I love the vignette you've set up on that wall but it isn't working with the stairs. The vertical lines are a direct contradiction to the curvy stairwell. My second thought is to ask why you need to turn this lovely little foyer into a mudroom or storage closet? Even though the area is tiny, the lines are beautiful. I'd be making more of a focal point of the stairs by lighting them underneath and putting something really pretty there. Know you don't have room for a grand piano, but a unique decorative item could be stunning. Have you bought rolling storage bins for under the bed yet?