Possibly making the stairs more like a rubber mat? This would allow for wider usage on all types of stairs as it would fit into them due to flexibility. Just a thought. Or is your image a more solid form placed over the stairs frame?
Would the walking stick have an electric motor of sorts for increasing and decreasing the length? Or good old gravity at the sense of a pothole? Have you thought of the dangers of the walking stick jolting too quickly and possibly being the cause of falling? Just some thoughts. Cool idea.
Tyson, this is a great article because exercise is extremely important for preventing elderly falls. I happen to know a Community Outreach Trauma Coordinator that teaches Tai Chi classes to elderly. Maybe consider Tai Chi as well because it focuses more on movement of legs and arms, however Yoga is also very helpful - its just they both might work on different things.