[Hatman]

^^^^
Some very interesting thoughts. I like your solution to malicious traffic-blockers.

I've heard many people worry about autonomous cars circling endlessly while they wait to pick up their owners. I've also heard many people worry about what will happen to all the public parking, especially street parking.

If I were in charge, I would do several things when autonomous cars go public:

1) Change all street-parking to Pick-up/Drop-off zones, at least in commercial zones. In medium traffic areas, set a time limit that a car can be stationary in the P/d zone. In heavy traffic zones (downtown) put a price on how long a car is stationary in the P/d zone after, say, 30 seconds. Your car has been stationary for a minute? Pay the city a dollar (two cents a second). Or whatever other price gets people in and out of cars quickly.

In residential zones, there would need to be local ordinances about street parking - such as having the residents come up with a list of cars approved to park in their neighborhood. Each person would submit the licence numbers of their friends and relatives and etc, and they would be allowed to park within X distance of that person's home. Anyone not on the list would not be able to park there - only P/d.

In a fully autonomous world, I see parking as a separate business, not as an amenity offered by private businesses or by cities. A large parking garage built somewhere out of the way will charge per use, or by monthly memberships. There will be no such thing as 'free parking' anymore.

2) Implement charge-per-distance road pricing. Keep the gas tax because gas produces air pollution, but don't use it to pay for roads. Instead, let roads be paid for entirely by the cars that actually use them. Autonomous cars will have to record exactly where they went, when they went there, and how heavy they were. This will all be added into a pricing matrix and then the bill will be sent to the owner.
Hopefully, this should solve the circling problem.
Obviously some roads, such as residential roads in small neighborhoods and the like will not ever be self-sufficient, so they will always need some sort of subsidy. Hopefully that will come from the local area.
Remember, roads designed for autonomous cars will be narrower and calibrated specifically for certain weight groups. Neighborhood roads won't need to be thick enough to carry a semi truck because a truck will be programmed never to go there.
3) Because autonomous roads are narrower, use the left-over space for bike lanes and wider sidewalks.

Just some thoughts. I'm very optimistic that a future of autonomous cars will be much better than the status quo. Imagine a world without surface parking lots, and with a bike lane running down the side of every street! That's the kind of city I want, and if enough people want that, and are willing to stand up for it, autonomous cars cannot possibly destroy the world.