When Photographing vehicles one has to take into account the reflection, Compose the reflection as they would a photo. The same thing applies to photographing a reflection specifically. Compose the reflection like it's own individual photo with a subject matter, be it an object or just a distant landscape. You can accomplish this with different locations and/or angles of the car, if the image in the reflection is uninteresting or distracting you end up with a photo that just does not seem to go over well like this one has.
Congrats on the new car though.