At New Orleans MSY, there's a passenger waiting zone on the ground floor of the garage opposite the terminal. You wait there until your driver is nearby. There's also a nearby section with a couple of dozen parking spaces reserved for Uber/Lyft, the driver pulls into one of those spaces to wait for you to walk over. These aren't for drivers awaiting hails, only for those already matched with a rider, so there's plenty of space, no stress about rushing to find your car that may be blocking traffic, all fairly relaxed. One slight improvement would be to number the spaces like the rental car companies do, so your driver could text you "I'm in space #11". But it's the best system I've seen.
Of course, it requires airports to give up that number of parking spaces in the hourly or short term parking area, but when you're charging $2-$4 per airport pickup, that seems reasonable for them to do.