I could see maybe #1 being a good idea, if the cost isn't too high.

#2 would make the farm lobby and ADM VERY happy. Don't know how effective it would be until we got better ethanol/methanol production methods.

It is impossible to build a car that weighs 70 percent less that anyone will buy, or could afford. I'm sorry, but most families need something that's a bit bigger than a roller skate.

You have no frigging idea what car companies have done to shave weight over the past twenty years. It's one reason my van is falling apart--stuff is made from plastic that used to be made of metal. There are composites, aluminum parts, and other things. All have to be balanced against cost and durability.

Reducing the number of cars by 70 percent by force would light off a revolution. Good luck with that one.