Hmmm... What would you like to store in this space? I'm assuming the brooms and mops are a "must". And I see office/school supplies. This must be your starting point. But the first thing you need is lighting. A couple of LED fixtures could be suspended from the ceiling or mounted on the walls. Check out GE's Albeo series.

Next: paint! White is fine for the walls, but why not prime that pine and paint the risers an interesting color? Paint the treads with a durable, washable paint in a matching color. Replace the hooks with something more attractive and utilitarian. Paint the pine boards the same color as the wall. If you paint the boards white, the plastic broom holder will disappear. The step stool can be hung underneath the brooms (hang those brooms upside down to save space).

If you don't use the attic much, and aren't storing anything large in there, my next idea is to add shelving to one side of the stairs. IKEA's LACK series is great. Organize your office things in magazine files and boxes. Label everything. Place boxes and baskets on the stairs underneath the shelves. If this is too much of a tight squeeze, stick to just the boxes and baskets. The Container Store has a zillion ideas.

Hope this helps! Let me know.