Character concept WIP, critique needed

tkalamov

Hello all. I have recently started practicing rendering and decided to mix up the usual figure studies with some over the top character drawings and paintings.

I have not decided upon a background yet, but I don't think this piece is more than a concept, so I think it will be something basic, an idea for a later illustration.

My main concerns are what aspects of rendering can I improve to show the form better, whether my understanding of form itself is at a good enough level to even be attempting this, and the general lighting and shadow structure. Proportions are always a concern, of course...

Feedback would be much appreciated!