raptor|3D,
Good to see your update! I think that there are some noticeable improvements. 
Books which I would recommend to anyone and which I will recommend to you are any by Burne Hogarth. He has a way of breaking down complex form into simple shapes that make it easy to understand.
Here is the link to Burne Hogarth’s books.
I think you have quite a nice line drawing here, but I think in areas, particularly the face, there is a bit of depth missing which I think Burne’s books might help you to see.
Mike / default.rol has been posting Master Copies from his books on the Master Copies thread on pages 9 and 10 here. Check them out to get a sense of what Burne’s drawings look like. 
I think you should go ahead and start shading. But I think the thing which both you and Slux need to work on is loosening up a bit, and getting something of the gesture in your drawings. You are both technically really good, but you should try to give your drawings more of a sense of life by using more fluid and loose lines ~ not to say inaccurate lines, but lines which ‘breathe’.
You are doing a great job ~ I look forward to seeing your update! 
Cheers,
~Rebecca




You have some nice work with the shading here, although I’ve also seen you do even better shading in other pieces. I think given the short amount of time, you have done a really nice job with this piece.