I like the morph effects of the Shape Tween. For the Motion Tweens, I like that you use symbols and can swap symbols--that helped me switch out my shapes with ease. Having an organized library helped with the swap process as well.
My favorite part of this little movie** is the dancing feet on the big red heart! :)
**I wasn't able to upload the .swf file - I gave up after it was processing for more than 1 hour!!