Safety?
I can remember when I was younger (senility hasn't kicked in yet!). The TV was awash with adverts about "Only a fool breaks the 2 second rule".. Which probably gives a clue as to my general age. However, this is something that PREVENTS accidents by actually giving people a good rule to follow to be far safer.
Pedestrians had the Green Cross Code (and some character called 'charlie' if I remember aright). Sod this "Well, if you get hit, call this number and you can make some money out of it", it actually told people "Be responsible, don't get hit. Pointless being 'right' but dead, just be safe", without all the over the top HSE stuff we have today about tying your shoelaces the right way and wearing 4 types of safety jacket and a helmet before going near a road.
Real safety comes from within every driver, not by applying oppressive force from without.
Personally, I think getting a good ad agency on board to revamp the old ads to apply to a more modern setting would be a big win. Give some good rules of thumb for people to apply (and make them seem like jerks if they don't; a lot of the drink drive ads do this, which is why it's largely socially unacceptable these days to get trollied and drive).
Give people something sensible to look at, and let them see why it's sensible, and they'll likely modify behaviour (in the main) and follow good practice. To catch the others, you need eyes (or at least a good "dangerous driving detector", and yes, it's possible with current image/pattern recognition techniques to identify this; just a lot more expensive than a Gatso) on the road to stop the real dangerous driving.
For "speed to kill", you have to have the accident first. Lets concentrate on stopping the collisions (the cause) rather than arbitrarily taking a hard line stance on speed (which is nothing more than a 'contributing factor' as the road stats have it listed).