Just a few observations...
Did the mansion quest yesterday. Was fairly easy. No complaints and fun.
Adventureland Quest - did it the other day. Had multiple problems with the number of other people also doing it. Went through the ride to collect the jewel at the end. The first time, I got bumped to a door 3/4 of the way through. The second time, I collected the jewel, but then took the teleporter to get out of the way of some other people. Of course I got one of the trivia questions wrong, so had to go through the ride a third time. Unfortunately, I learned that it doesn't pay to get out of the way of others.

Made it through to the end, and thought I had the clue figured out. Went to play mini-game. Win the game - decent score 10K+ - nothing happens. Well it didn't say anything about a minimum score, so I must have the clue wrong. Try another mini-game. Try visiting Blackheart. Try going back to the pirate ride to see if I missed something. Ask in the lobby. Told that it is mini-game. Try again - score 15K+ - nothing happens. Go back to the lobby and ask again. Keep trying, I'm told. Next game - score 19K+ - finally finish quest. My only suggestion is to let people know what the minimum score is, or they won't know they have the clue right. Either make it a cryptic clue with a low score, or a non-cryptic clue with a high score - not both.
Tried to do the Frontierland Quest. Too many people were doing it, so got stuck on the clover maze. People were getting nasty, telling others to move!, etc., so I just gave up on that one for now.
Started the Expert Quest. Thought I should give it a try. (I actually signed on to this one a few days ago, but quit to play other quests) Last night I was having a good fireworks game, and managed to beat the score on the first task. Excellent, I thought! Good Work. Next task - fireworks magic in 30 seconds or less. Not wearing it - 300 pins to look through and find it.

I bet you can guess that I couldn't find it in time. Now I have to start over. Maybe either increase the time to 1 minute or more, or let people know which pins they should be wearing to start the quest. (Although I suppose this quest is designed to make you go back and repeat steps to make sure you aren't getting fluke scores - I would be interested in your thinking on this one)
So, overall enjoyable - and I keep coming back, so I guess that's the litmus test. Thanks for all your hard work in setting up the quests.