Ugh, it's been too long for me to be away from graphics. This is really amazing. I really like the [I don't really know if you were going for this,] three-dimensional feel of the whole piece, and I really like the contrasts of colors. c:
It seems too dull to me. Empty. Try adding more colours next time? Especially to the background if not the render. It needs to not look so flat and faded out.