[rz2k]

Drivers are eventually going to follow pretty closely what the metering algorithm wants them to, with a moderate adjustment for passenger satisfaction for the sake of tips. Consider different per fare starting fees, and different per mile and per minutes additional fees. If the fixed revenue part is relatively high you'll end up with very fast, but probably unsafe, cab rides. High per mile rates and you'll possibly end up on unecessary freeway legs. High per minute rates and you might get dropped where there are a lot of new fares rather than where you want to go.