I'm a lifelong F1 fan (I remember Hunt's championship season).
I'd budget cap the teams (severely) and draw up a formula with driver protection and safety at it's core. After that, anything goes. Turbos, massive wings, moveable aerodynamic devices, refuelling, KERS, traction control, ground effect skirts, turbines, CVT, ABS, warp drives, whatever.
If you can design and build it in budget, you can race it.
Alternatively, the higher your declared (and audited) budget, the fewer the points you score per position.
It'll carry on as it is though, corporate junkets and hospitality being it's prime mover.