Looks like you may already have a little bit of color blocking going on, but I'd increase the contrast between the shades of paint. Do you have access to the original paint chip card? Paint two of the walls in question in two different shades from that same card. Consult with the paint source for the complimentary color to accent the third wall. I think the middle wall to the right of the stairs would be the one I'd accent. Then add a large piece of colorful abstract art to that wall. Here's a quick tutorial on color blocking. https://www.houzz.com/magazine/building-with-blocks-of-color-stsetivw-vs~639

http://www.simplifiedbuilding.com/blog/space-saving-stairway-shelving-and-tv-mounting-system/ Is this what you had in mind?

Best thing to do is to enter search terms in the Houzz search bar and review photos. You can save those that you like in an ideabook and you may end up mixing several ideas to get what you want. Try different terms to filter photos.

There are actual rules about staircases as to riser height etc so best to get an architect involved in the process this will take up a lot of sq. footage too.In many places a spiral staircase is not allowed only if the elevator can hold a stretcher