He is a little bit lean... for a cartoon, which tend to exaggerate a bit. I like where it's headed...
The front knee (left side) has an odd shaped kneepad.
I see what you mean about the sideburn. I think that's a poor choice on
OSU's part, but admittedly it might look empty without that there.
I'd also be curious to see how it looks without the fire/whoosh effect as he runs.