You need to drop a lot of the safety, grossly raise the price, or both though.
I've got some family in the auto industry, and their consensus is that we are either really rapidly coming up on the point where we've got just about all the safety and fuel economy we can have without sacrificing safety, or we're already there. You're getting into the space where arguing for increased fuel economy is going to be directly arguing for killing more people. You may find this a tough sell. Especially since telling the automakers to "make less safe cars" is also going to have to come with an ironclad guarantee that when people die in these cars, the car companies won't be sued. And getting that law passed is going to be a tough sell, too, for a lot of reasons. The safety advocates aren't exactly going to stand passively by while you try to tear their stuff apart.
Basically, you can't have it all. Not even if you pass a law saying that you have to have it all.
And while we're at it, let us also not forget that "grossly raise the price" also is not something you can just wave into being. The Democrats can hardly try to make "inequality" into a major issue, then do something that unambiguously makes cars much more expensive for everybody.