The main problem is scalability... Taking 30 minutes a charge is fine, as long as people know the etiquette. e.g. don't leave your vehicle after it is charged, as others need to use it too.. and if you're on a waiting list, then that is going to suck because at most you have to wait 30 minutes, and then another 30 minutes, and so you are now into an hour to charge.
It might be better to start moving to autonomous electric cars at that point..