A week ago, the first part of the checklist listed some things to check when you finish a track to see if you did all you can to make it better. The list continues here…
11. An intro clip: is there a 10 to 20 seconds introductory “movie” that introduces the track? Does it show the key (or the most interesting) part(s) of the track? Notice how every track in Trackmania Nations Forever has an introduction consisting of (usually) 3 short camera moves, one showing the overall track, and the other two or three showing key areas — try to do the same for your track. But don’t make the intro too long.
12. Is there an outro (replay) for your track? Will the player be rewarded for finishing the race by seeing himself in action from interesting view angles?
13. Does the replay work reasonably well even for a worse driver? Make sure those who are slower can still see themselves, and if a longer replay clip tends to “run away” from a slower car, cut it into two or more partial clips so that those who can finish can also see themselves in the replay. An extra benefit of this approach is that Spectators in online races can then use the Replay mode to observe other racers!
14. Light trails: Have you considered adding trails to jumps? It looks pretty awesome, especially in night and evening mood tracks, if you approach a jump during online play and see the colorful stripes ahead of you, showing you what’s gonna happen.
15. Finetuning (smoothing): After you’ve driven the car enough times, you might have noticed some areas that are not perhaps the smoothest possible. Don’t hesitate to take an extra time making them smoother. It does not mean “easier” — if you have a sharp turn that was intentional and the player is warned that it’s a sharp turn, then it’s OK, but if at certain combination of speed and angle the car just bounces off of a landing platform, then something’s not right.
Well, that’s my tips for making your tracks better, but I’m sure there are other tips that you use. Please, share them in the comments!
TrackMania United! 
The first part of the article can be found
here