Radman : My daughter has been in and out of the chair for a few months while recovering from simultaneous injuries to BOTH ankles, so I am getting some insight from her on that. One of my clients is a non-profit that works with people with disabilities, so I get to interact a lot with their clients while I work on the computer system. Those are the main reasons I chose the topic, I have some previous inspiration and will get some technical advice from long term chair users. For some of them, this will be the first time they have ever been asked for advice.
Since this is a first year project, I don't want to get too complicated, and I doubt the materials will stay on the chair permanently. Once my daughter is fully recovered, we will likely pass the wheelchair on to someone else who needs it. GPS/Fitness would be cool, but as you say, likely a bit advanced.
Sail: You are right, that would be cool, but not really an Arduino project.