Hey that looks pretty good.
I've been modeling vehicles for years, taught CAD stuff in the Ford design studios, worked at Chrysler, even the Aston Martin design studio in England, all sorts of stuff, one car I surfaced was on the cover of Road & Track the other year. All sorts of detail stuff I can't talk about due to corp confidentiality agreements...
One of the challenges are the reflect curves or highlights. Blends of curvature that gives shape. A great advantage of surfacing tools like Alias or ICEM / ISD is the advantage for real time editing of the surface geometry and manipulating the highlights. I can't really critique your stuff until you light it up with highlights, the flat color doesn't illustrate the shape that well with basic shading, and it wouldn't be really fair for me to do so either. Even down to not using constant radius fillets etc, need to wash out even the smallest of corners with conics curves, blending curvature from one surface to another which is the basic foundation of modeling. Then there are the highlights, giving some shape to some type of feature or theme, all sorts of illusions and techniques that the artistic creative folks in the studios sculpt with reflections, there are even some that are a corp proprietary design or a theme. So many vehicles today are comprised of features from others.
There's always some type of competition going on, for example:
Car Design Competitions - Car Body Design
In the studios, there's typically the designer, the artist that uses some tools like photoshop, and then there'e the surfacing person using Alias or ISD / ICEM. I've been more of that surfacing type of person, creating the 3D geometry (most of my experience is in CATIA for 18 years, and ICEM embedded into CATIA which is ISD)based on the renderings and clay models, making changes or whatever, more or less translating the artist's vision into reality...
If you already know most of this stuff, don't let me offend you, I don't know what your background is, I just read this post and started babbling.... Feel free to shoot a PM, I have all sorts of connections in the automotive design / CAD world.. and would enjoy helping out if I can. You obviously have that passion if you are doing it at home for the heck of it to challenge yourself, that's great!
Best regards,
Mike