Constructive criticism, eh?
I think the most important thing anyone can tell you is that you need to be more confident in your work. This flash is easily one of the best I've seen in terms of detail and animation, and you could teach a lot of artists on NG some lessons about content and detail. And remember, most of the people who write these reviews probably are bitter perfectionists anyway (present company included :( ), so why do you need opinions from peple like me when you are obviously good?