(Yeah, I know it means putting an actuarial cost on a human life, but statistics means mathing things up.)
Sadly for the rest of us, it's not exactly easy to get that data from the insurance company.
[Edit]: found the policy: death: £2,500 arm or leg: £2,000 blindness in one or both eyes: £2,000
If the current state of commercially available ADAS was dramatically reducing accident rates, then Teslas etc would have lower insurance rates. And yet they instead have higher insurance rates.
Tesla's have had higher insurance for 5+ years. Some of which is due to wait times on repairs, costs of repairs, and also accident rates.
Or, when you do have an accident it's typically more expensive to repair.
In collisions that don't involve pedestrians, the damage to the car/object is generally proportional to the chance that someone was badly injured or killed in those cases - the only thing you get by adding human life costs is to take into account the quality of the safety features of the cars being driven, which should be irrelevant for nay comparison with automated driving. In collisions that do involve pedestrians, this breaks down, since you can easily kill someone with almost 0 damage to the car.
So having these two stats per mile driven to compare would probably give you the best chance of a less biased comparison.