What an imaginative song idea and your vocals are free and expressive. There`s a sense of theatre in this which reminds me of the best songs from animation movies... and that`s the only thing that occurs on the production- I like the tiger growls and felt you could have done a little more in the sound effects dept. to set the scene.
Not a plug, but I had fun making a circus song a few years back and found some cool loops that fit.

Robert