Simple steps:
1) Ban/limit refuelling - control power/speed by limiting total fuel allowed.
2) Ban all driver aids - make the driver drive, not the car.
3) Allow turbos back (1) would prevent stupid powers. Variable boost would allow more power when you wanted it but you will run out of fuel if you use it too much.
4) Optionally limit downforce - car in wind tunnel in clean air at 50, 100mph, downforce must be less than 50%, 100% of car weight for example.
Just ideas !
I like these, and the FIA are comming close. Not sure about limiting refuling, but going back to qualifying on low fuel to allowed the grid to not just be everyone in race order would help overtaking. All driver aids should be banned. Dont know about turbos, the engines are that far apart... And downforce definately needs to be reduced, which the FIA are planning for next year, along with a move back to slicks. all these changes were to make the sport safer, but now they are goiung back as its alos made the sport boring.