This is a crit I've given for another run animation, and I think it applies here too. At least, I have found it usually looks good.
Try making the arms snappier. That is, right now they move at a constant speed, and then at the height of the swing they immediately reverse their speed. If they move faster at the bottom of the swing, then delay at the top of the arc a bit, I think it would make it look a bit better.
This is fairly minor, and I like it overall. Good work.