Oh, I would probably be doing the same if I were a motorbicyclist.
The point is, you have a group of road users who have no regard whatsoever for the speed limits and they are endangering themselves and others. Do you:
1) Put some effort into enforcement, and make an example of a few of them.
2) Use it as a fantastic excuse to slow everybody else down, then start making money from people who mostly observe the speed limits when they aren't insanely low. Meanwhile, continue to turn a blind eye to the dangerous offenders.
Must say I am with you on appropriate use of speed, rather than 'think of a number and halve it' limits... if you have a two mile straight with no junctions and reasonable visibility, then does it need a limit? The Acle Straight on the A47 is a good example... there are two principle hazards on that road, oncoming traffic and a slight bend halfway along. Obvious solutions are make it compulsory to use headlights at all times along it, and mark the bend clearly in order that someone approaching it at 100+ mph actually has fair warning to slow down for it. This could include reactive signs triggered by vehicle speed, displaying 'Ease Off now', 'Brake now' and 'Too Late'. Make the zone a quarter mile either side of the bend 40mph, with a camera each way. Also include a limit, of say 60, together with a ban on overtaking if it's raining/foggy/freezing
Wrt your summary of the solutions, obviously 1 is the sensible approach, and 2 is the actual approach
As for paramedics wasting their time looking for bits
Send an ambulance for the other people involved and an black van for the motor bicyclist. To be blunt, and apologies for that and for those having lunch, if someones head has come off, then despite the best wonders of modern science, they are dead
So have someone else collect what's needed to identify them and leave the paramedics to dealing with actual casualties... no wonder you can't get an ambulance when you need one