So if the player dies a lot you could make the level easier. If the player ignores enemies and treasures and prefers flow over completeness you could create a level that focuses on these aspects. The level generator I created encompasses all these aspects. For example, compare the following two jumps:
The former is used for players who died a lot whilst the latter is used if the player is somewhat competent. For players that seemed to like jumping I could create jump-tastic sections like:

For variety I added different sections like caves:
A typical map would look something like this:
Evaluation
In the competition I came third: http://www.marioai.org/LevelGeneration/Results