Air-conditioning fitted to the seats.

I experienced the joy of cool goolies on a hot day in a pal's jag.

Air con is nice on a blazing hot day but does nothing for Betty Swallocks on a hot leather seat.

Or a sweaty back

Greasy fingered oxygen thieving scummy pond life would soon find a device for blocking emitted signals.

There's probably something already out there.

Decent car thieves aren't troubled by any tracking device.

Standard fit in all cars should be an electro-shock device in the drivers seat to gently remind nobs that slowing down to watch the AA rescue someone on the hard shoulder is a gunt's trick

Yup, most have kit to block or locate trackers.

You can even get blockers that plug into the cig lighter with an aerial and will block any mobile and GPS for 10ft according to a recent channel 5 documentary on car thieves

Rain repellent glass for the windscreen should be standard

 

There must be a way it can be made part of the structure of the glass rather than needing to apply a coating