I forgot to post WIP videos of this assignment. I was maybe too much focus on this assigment. I understood a lot of things concerning my common mistakes. In my opinion. Can't wait for next assigment to apply everything I learned :P
Edit: I did a render and I admit I love this shot even more since it is rendered. The background has been done quickly from a free HDRI image. I also found a tutorial on lighting which is really simple and easy to tweak.