It would be fun to see what the engineers would design and build if the government would get the heck out of everybody's business.... The majority of people who buy new cars don't care and wouldn't even know what a space frame was. All most of them care about is that drives nice and is quiet down the road so they can hear good when talking on their cell phone while the kids are in the back watching TV with their headphones on..... As far as a space frame with a composite body, people would never pay what it costs to produce it.... Simple economics.