You should to insert more frames for a fluid animation to extending the oscillations on right/left because now look like a translation. To understand at the best the animation rules, you can apply at all that is animated, the 12 principles of animation: http://www.animationtoolworks.com/library/article9.html Take a look. With this your animations become fantastics! Bye!
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Love the bounce but the wobble looks weird. Did you remember to antialias the little splitting point during the wobble?