Yes, if the driver gives good service, like helping me with packages, I will certainly tip, and I want all of the tip to go to the driver. Hell, maybe I'm unusual, but I normally tip at least 20% as long as he's ontime, clean car, and doesn't take the long route.
Maybe my small city is unusual, our two taxi companies are pretty honest, they wash and vacuum the car each shift, no driver smokes, and the wait time can be as little as ten minutes from when you call, up to 30 minutes if they're busy. The trick is to call earlier and make a reservation. Then you've got a 99 out of 100 chance that the car will be there when you need it, and probably earlier.
I looked up several of my regular taxi rides on Ubers find your fare page, they were consistently a dollar or two more than I pay for a regular taxi. The booking and other fees alone add up to my home to work taxi fare before the mileage is added, making Uber the high cost provider. I want to study the pricing a littlemore, probably on longer trips Uber will be cheaper. There's got to be a sweet spot, because they charge only half the per mile taxi rate.