I would have likely found a solution had I spent more time on the preview icon (I spent about a minute at most), but it's only purpose it to trick the viewer's expectations.

Oh, I actually had very same problem when drew knight in post from 11th of september:

www.pixeljoint.com/forum/forum_posts.asp

When I drew cape with plain color, it was not contrasting enough to show the body right. And when I used outline for cape, it was hard to understand that it is a cape and not the frame or something. So I erased it completely. Maybe there is different solution, but I don't know about it yet.

"Ace preview (but it would win more if the sword would be more articulated - now it touches the ground -> looks like a stick of an old man)."

There actually isn't a sword in the preview icon.  That's probably his cape you're referring to.

I see that this effect may appear in transition from red to black, so it can feel that black separates body from the air (not from shaded area of the body) and naturally folds of cloth transform into traces of the wind. But my initial feeling was that he stands still. It depends on perception of viewer.

Ace preview (but it would win more if the sword would be more articulated - now it touches the ground -> looks like a stick of an old man). And main pic looks great!

I am actually having trouble seeing how the line based dithering shows that, I was hoping the pose would be what shows battle readiness, heh.

I've had fun playing him in Dissidia! Nice in it's simplicity. The amount of little straight lines in the pic kinda make me feel like he's dashing forward, ready to slash.