After 50 some votes, the only Poll option with no votes - "Has a satisfying conclusion" - is the one I had in mind all along. :lol: Like several people have already stated, a successful attraction combines many (if not all) of the elements listed in the poll. What I was trying to get at is which of them takes precendence.
In my opinion, having a satisfying conclusion trumps all other items. The ending needs to fit what has been set-up - fully addressing the story, suspense, and anticipation built up during the attraction. If I walk away from an attraction and don't feel satisfied by the ending, I'm unlikely to ride it again. Even if the rest of it was entertaining and well done.
A cohesive story with great characters and wonderful theming will still leave me unsatisfied if it doesn't end on the appropriate note. Now, it's impossible to have a satisfying conclusion to an attraction with no story and no theming, so certainly those elements must be present to some extent.
However, if I were an Imagineer, I would work from the concept that first I must have a very satisfying conclusion, then I'd work on the other elements.