— Elimination of the minimum height rule. That would be to end the rather meaningless post-race controversies and penalties for cars being 'too low' after a race. Some worry, though, that such a rule would force teams to discard thousands of dollars of expensive springs. However the current rules have led teams to spend huge sums on very trick springs.
— Adding roof 'wickers,' similar to used in years past, designed to break up air flow over the roof and presumably make it easier for a trailing car to pass. Mike Mulhern.net