It seems like a better solution would be to have multi-ton zeppelin-carriers which hold a host of smaller drones that can carry packages of various sizes. You f

It seems like a better solution would be to have multi-ton zeppelin-carriers which hold a host of smaller drones that can carry packages of various sizes. You float from city to city, moor the zeppelin, and your delivery fleet swarms out to deliver the packages. It would also probably travel slowly enough to service flyover counties by...well, flying over them.