I like @kelly's idea of picking a lovely fresh color of paint for the door. You can then bring it down onto the stair risers. Either a solid color to match the front door, or go wild and add some decorative elements to the risers with stencils. Or think of staining the door a great color and coordinate the stair railings and risers. I have an idea book put together for just such project that might spark some ideas for you. http://www.houzz.com/ideabooks/16700983/thumbs/Kathryn-Delany-s-Decorative-Stair-Risers

Thanks Susanne_m, that is a really great idea, I am actually in the process of painting the frames so I am sure I could get one more, my Dad loved Norman Rockwell and bought them for me all that time ago they have been hung in our house since our children were 3 and 4, 40 years ago, great idea, will go searching now for frames!

What did you end up doing?

Joanna Gains style is fun! What you choose for lighting and surfaces will determine the amount of reflective light in your stairway. The Architect is right in what he is suggesting "a decorative wall" could bring more light into the space. I believe you could apply this on principle....for example you could do a feature "Architectural Mirror"or lots of mirrors on the wall in the right position to reflect light in "Joanna Gain style" then in the same style add an eye catching pendant or wall lights depending on what is best functionally. Remember what you use on the ceiling & walls is important too every surface counts for your situation. Try a satin finish with a cool white like Dulux "St Clair Quarter" or Resene "Black White" Maybe Nancy's suggestions of a skylight is an option for your situation if it allows ? Natural Light is always great. Heres some inspiration...All the best!