Pull out Wardrobe Rail for under stairs. You could have a few of these attached under the higher stairs and some storage boxes or even a chest of drawers underneath, then you could do away with the black frame and the room would look / be much larger.
Here, off-the-shelf storage bins convey color, pattern, and travel inspiration with the help of old maps, matte-finish Mod Podge glue (which becomes transparent when dry), a paint brush, and a putty knife to smooth out bubbles. Something to keep those gardening magazines in??