Only thing I saw from a animation standpoint is the tie's softbody (as well as the skirt at times) had a weird error and would bounce. I guess that would probably be the physic's fault.
Also adding a few more facial expressions prior to the actual singing could be beneficial, the first and last 10 seconds are the most important part to any media device.
Slugheady already mentioned ankles, and someone else the hair, but besides that utterly amazing, especially for just a test.