Would it be possible to have a non-spec series as fast as 2004/2017 F1 cars at 1/3 the cost (and maintain similar safety standards)? Say engine, chassis and aero all done individually at an annual budget around $100M USD?
Could there be aero rules that allow for plenty of downforce but leave cleaner air for cars to follow each other closer.
Would big steel brakes (in tandem with active-aero braking?) work to double braking distances and allow for more passing?