Before someone jumps on my neck, I'm not bashing neither Flash neither Sic. Any attack to me about my feedback will be replied strongly.
He is my buddy and can handle criticism. But if you don't, back off. 
Ok, here we go.
What I like:Overall, its a good char. His trademark high speed is present, which makes him pretty deadly.
That hypermove where he travels the world was a pretty sic-k (forgive the pun,
) idea.
Even I'm not beeing fan of constant afterimage, on this case fits perfectly.
what I don't likeToo much static edits. The same head (same position) where pasted in 80% of the char, which gives a weird result.
Take a look (I've reduced the frame speed) and pay attention to the head:
Some moves needs more movement, because just some parts moves where everything stands still (again, the same head):
(the thunder signal moves)
The movement of his torso is pretty weird. Its not a good position to land a punch.
This move needs to be redone, because the anim stops too rude (he needs to bring his leg back or to spin to the original position).
And the clsn are totally wrong. When you use a DefaultClsn, it would be used on all animation. But if you use a Clsn on another frame, that clsn will CANCEL the Default Clsn. Take a look at the second image - where is the default (green) clsn?
(plus, the blue clsn needs to be a tad higher)
well, I think is all. Besides those errors, the char has a great potential.
Veterans Day