AndrewR,
You say one passenger fatality in 5000 missions is high. And yet we accept (in 2016) approximately 1235 people killed in fatalities on Australian roads.
No calls for mandatory recurrent testing for drivers licences (say, every five years you have to re-sit your drivers test).
No calls for mandatory specialised training for those who want to tow a caravan (including how to reverse a caravan).
No calls for mandatory training for driving on gravel roads, driving in stormy conditions, driving at night.
Why are these training requirements mandatory in the aviation world, and yet not mandatory on the roads, which affects more people?
Because driving a car is seen as a right, and flying a plane is seen as a privilege. Yet both are just means of transport.