If you are looking for storage and a mirror, why not get a nice bureau with a mirror; or, get a storage unit of some kind, put your cutting board or ironing board on the top, and then add a mirror on the wall above it. I would put rollers on it so you can move it. You could also use the stick-on mirror tiles. I would definitely add shelves to the wall above the sofa and behind the exercise equip. Consider the white melamine shelves because of the color.
Also, as a suggestion, you could put up the shelves but add the strip lighting, or the rope lighting. Either way, go for it, make it just 2 or more colors, even throw something over the dark sofa, like a quilt. That would take care of the dark color. If you put up a large shelf with a mirror under it, put up a daylight florescent under the shelf. Enjoy!