If F1 was totally free technically, what would evolutions would you love to see?

I was thinking about some of the more egregious technical loopholes of the past, and realising how much I missed those cheeky interpretations of the law.

The six-wheeler Tyrrells from the 1970s, fan cars, moveable skirts, crazy high revving engines with exotic alkane fuels and berylium parts, the S duct, McLaren's second brake pedal, Benetton's launch control software, tire doping, ride height control, rear-wheel steer, DU in the wing planes...

But there must be also new areas today where engineers could go off piste if they had the freedom, in areas like the PU, charging, energy release, fuel conditioning, bizarre aero, cockpit shells, driver-controlled adjustments, AI-assisted suspension control. What would you like to see?