Rayman Adventures has time trial levels which could be included, but it's hard to separate them since they're not named. There's also the potential issue when using Incrediballs to reduce your final time etc. As for the Sacred Tree height, I think that would be a bit unfair considering some Incrediballs don't appear for all players (possibly a glitch).
Also, I was thinking, maybe we should remove all the "game completion" leaderboards from the page since they seem rather unnecessary. Most players have 100% completed the games anyway and it isn't really a "leaderboards" since there's a max amount of percentage in each game (except for the games with scores, like Rayman 3, where obviously the leaderboards should be kept). Any thoughts?