I feel like a bid/ask function wouldn’t be that technically difficult to implement.
A driver can punch in minimums: Maybe there’s a driver who is only willing to drive for $10 per ride, $0.50 per minute, and $0.25 per mile at a particular moment in time, and maybe a multiplier or premium for certain routes that involve tolls or larger passenger groups, etc., or a discount for pre-booking at least certain number of hours or days in advance. Maybe the pricing could take into consideration more variables (idle time versus driving time, pickup distance, minimum rider rating, etc.). Potential riders punch in their desired routes and they get real-time pricing information on the available drivers and the quoted price according to each driver’s formula.
The formulas shouldn’t be that hard for the driver or the passenger, from their interface, as long as the service has access to go route data.