well, don't really need anymore rules.
How about start relegating or even disqualifying guys who don't hold their lines in the last 150m from the finishline? Enforcing this one single rule alone consistently will decrease 95% of the crashes. Guys would be allowed ONE single move, but after that they must hold their lines to the finish (similar to Formula1 block-pass rule, you're allowed to make 1 move while passing, that's it, no weaving back and forth).
Now the other issue is the the leadouts. You just never know how or where these leadouts will peel out. In come really bad instances, the leadout will peel out and sweep across almost an entire road. There must be a consistent rule for leadouts to pull out safely and expected. I suggest that leadouts
1) must peel out 150m from the finishline at the latest (you'd need to mark the road so they know the 150m mark)
2) leadout can only peel to the right and only 1 meter to the right. This prevents them sweeping unpredictably across the road.
Also, a 300m straightaway to the finish will greatly facilitate the execution of the above rules. Cycling sprinting is the only highspeed finishing sports where
1) there is no clear sprinting lane (or refs will not enforce it when somebody crosses the line)
2) no defined rules for overtaking (allowing guys to dodge and draft at will, sometimes recklessly)
3) no straightaway to the finish
if refs start punishing guys, they WILL have an effect of raising safety.