Something is missing from the game 
For an early supercar, say, 1950s or 1960s, a popular way to design a chassis was a tubular space frame, made from aluminium or steel. Such designs were used, for example, by Ferrari and Jaguar.
In gameplay terms, a tubular spaceframe would be light, stiff, but very expensive. It would mostly be useful on a high-cost sportscar or supercar. But I would like to see this option in the game!