Recently I dabbled in a bit of rFactor 1 racing, and I crashed a lot. What I found interesting is that in rFactor some basic parts of the car detach when crashed ie. wheels, front/rear wing, sidepods and similar.
Of course it doesn't happen always, just with major high-speed crashes

I think it'd be pretty neat to have something similar in Live for Speed

Agreed

It has already been suggested before and it's in the summed up list. This is still far away due to level of difficulty on the game engine side.