Carpooling is ok, but thinking about where I live, I'd totally go for owning a self-driving car. My wife works about 10 minutes from home, I work about 20-25, depending on traffic. She leaves a half hour before I do, gets home a half hour before I do. Car could drop her off at work, come home, get me, drop me off at work, go home, and park in the driveway. 10 minutes before she heads out of work she can summon it, and it will take her home. Then 20 minutes before I want it, I call it. Or I go grab a beer if she's going somewhere.
No street parking, no lot parking, no real need for 2 cars, no adjusting the seat, no sharing with strangers. If she's going to be at the yoga for an hour, the car can come get me, drop me off at home, and head back to yoga.
I think this means a bit more congestion on the road, however. This should be mitigated by the auto-driving capabilities, and can be further mitigated by reclaiming parking for more lanes. We'd need a small fraction of the metered spots if cars could go park a little further away, and they could park in dense clusters, because they could move when one needed to get out.