Mirrors are good, but too many blind spots.
In last few years people close to me had 2 accidents, when walking on parking lot got run over by backing up SUV and car. Both cases ended with long hospital recovery after 2 mph incidents.
Than you can always send a passenger back there...
On other hand, European cars lately are coming with pyrotechnic hinges on the hood.
In case the car hits a pedestrian, the hood pops up to give additional spring cushion.
There is no limit how much safety you might consider necessary.