Great, I think you came up with the simplest solution: Uber should make whatever single digit percentage of total drivers that comprise their Uber Black drivers FTEs.

This might be a good selling point for the higher levels of Uber service: You're getting a full-time, professional driver who's been thoroughly vetted. It's not just some random person with an app.

I think for the vast VAST majority of riders, the "random person with an app" is good enough. In the age of turn-by-turn directions, rides are commoditized. A hundred crimes per year divided by billions of trips per year represents decimal point percentage crime rate — which is a risk not all that different from aircraft crash statistics, or even car crash statistics.

I know I definitely prefer to save tens of dollars per ride vs the services provided by some platonic ideal of a "professional driver".