2o6, i really, really like your overall design, specially the rear. It's very good.
I had already told you before that i think you have a talent and your designs are different from what we often see, and, better yet, are improving day by day.
However, i still think you should focus in your modelling details, since it seems you've chosen that way to show your ideas... I know is hard, time consuming, and sometimes boring, but in the end you will, certainly, be happier with your work. Keep read the tutorials available out there and try to follow them line by line. If you think it's better to understand some steps, try to model an existing car that you are familiarized with, and that way, understand the small subtleties envolving automotive design. In my opinion, better than quantity it's quality.
Nevertheless, don't give up with what your are doing, you are doing it well... But i know that you are able to do best!