Well, firstly you can't really say that anything I do isn't really possible, it would just take more time and money. I had a mate who had a Mini and he had the roof chopped, so that the windows were only 6 inches high, which looked cool, but wasn't very confortable if you were a passenger.
The main reason that I usually end up changing the shape is that I'm trying to create something that I think looks nice and, if I don't think the original car looks nice, then nothing I do to the outside of it is going to change that. For that reason I usually prefer my own designs to other people's, because I'm creating something that is unique to my taste, that said I don't think mine are the best, just the one's that appeal more to my taste. I appreciate that the idea is to do modifications that you might see on a car on the road or at a show, but since we are not likely to own the cars with the custom kits we create for them, then surely the most important thing is to improve our creative and artisitc ability and to improve our photoshop skills.
If people would rather I didn't enter my chops for the final vote, I don't have a problem with that, because that would at least avoid the possibility of me winning, but the votes I do get are nice, because it means that some people appreciate the work I have done. I realise that I am not strictly within the parameters of the challenge, depending on how you interpret them, so not entering the voting would be acceptable to me.
I think more of an issue is that more of the entries seem to be following my trend of shape changing, which might make the people who were willing to overlook my transgressions a little less likely to overlook things.
At the end of the day I do this for my enjoyment and my development. I certainly don't want to upset anyone by what I do, but I wouldn't want to do something that I didn't enjoy doing and creating something that I don't like, I wouldn't enjoy.