I believe those percentages are fatal accidents.
My house is a dome design, but not a monolithic, it is a design/construction method I 'invented' which has never been done before afaik, which is why I have not build it, in California no way they would let me on my lakeside property without outside certified engineering reviews that cost more than the house would.
Basalt is not even close to carbon fiber, they like to spin it that way, but it is maybe more like a cheaper s-glass, which is very overpriced itself.
Cheaper is better than lighter I think for this car.
I am planning to offer a few carbon fiber built versions in the kickstarter, just to give the people looking to send some money and get something special.
The molds don't need to be light.