This work is asymmetrical which is very nice for the eyes, however some of the shading i feel specifically on the gray areas needs some work. The legs on the other hand are shaded very well with many different colors. Perhaps add a background because at this point it feels as though the picture is floating for none of it is leaving the page. Use the entire page to get a great full affect of depth and form. With all this said I feel that with just a little more work your piece could be placed into a portfolio that you would use when looking for jobs.
I used to only do Traditional Art.......but somehow I got 'way-laid' with Photography. Since putting a lot of my drawings on, I have had great 'feedback' like yours. Making me want to start again. Thank you so much. Hugs