The copyright thing was just a thought, especially since USA Games were also working on a game which they had people turn up at the guy's doorstep unnanounced as I understand it with a lawyer. You would think a letter would have done the job. I didn't know how Eidos felt and so on.
As to making an easy to navigate level, personally I think it would probably be a good idea to have at least some way to have an idea of what direction you're moving in. As I have memories from before my sight loss of Tomb Raider 1/2 demos I would say something like a compass system which gives audio feedback would be pretty crucial, otherwise how do you know which way you're facing? It is most certainly possible, it just would probably take more than level design... though this is just my opinion. I couldn't imagine playing GMA's Shades of Doom or Tank Commander without the compass feedback myself.