Nice work, but i think the pixel should be 1x1 view, with that your artwork will be looks great. Also the black background is need to remove, using the transparent background would be better.
Yeah, I agree with Mikau; you've already got a shadow for the character (which I noticed after I did some background swapping to check if it was compatible with other colours or not) and the current black background only hides that.
Just make the backround transparent or the same colour as the gallery.
The only thing I can see wrong with this image is the pointless background. Could you please remove it?
Post it in 1x, we have a built in zoom function you know.
Fus-Ro-Daaah.