Research backlit frames (lightboxes) and work with the City to install them in Leo Roy and/or other garages. These lightboxes could hold art by students or by artists; advertisements for local businesses; downtown directory; or other visual media. These boxes can be found to be vandal-proof and high-quality and be placed where electrical already exists (lobby, staircases.) If installation expense is too much, work with City to put up posters as placeholders to rally business community or city for additional funding.
This would provide extra light and color, enhancing people's feeling of safety. It would encourage people to park in garages and walk around downtown. Most importantly, it would serve as a pilot for bigger changes in parking garages like large public art installations, colored lights, music, or other improvements that show parking can be fun!