Let me just express a concern about procedurally generated dungeons. While I like the potential for replayability with randomly generated layouts, I keep getting this nagging feeling that there might be a vested interest in that idea from some guy that would benefit from making it more difficult for others to beat his score by changing the racetrack.
Well, of course it could go both ways and someone down the line could get a map that's trivial to clear with all discoveries, but that's unfairness on the other end of the spectrum, no?