I will respond briefly to this rich set of comments.
Several of you raised the issue about whether potential drivers would have the information if a more complicated congestion pricing system were implemented. But clearly, information is abundant that congestion is greater during peak hours, on Fridays, during snowstorms, etc. so higher prices at these times would be an enormous improvement. Note that in many cities, parking on certain streets is restricted during snowstorms, and that usually works since parkers anticipate when the no-parking rules go into effect. The old adage "the best is the enemy of the good" is applicable. I am not advocating a perfect system, but one that would greatly improve congestion and reduce the time wasted in traffic.
London pricing is based on its central city as a hub, but the principle of charging for traffic during peak times is applicable to suburbs, Los Angeles, and other areas without hubs. Electronic pricing makes that relatively easy.
Parking fees are not a good substitute for congestion pricing because no parking lot owner incorporates all the costs imposed on others of driving into or in highly congested areas. Delays caused by people looking for on-street parking raises additional issues. These delays are created by parking fees.
It is not obvious that congestion fees are regressive since poorer persons are more likely to take buses or subways to work than to drive. Moreover, labor force participation rates are generally lower at the bottom end of the income distribution. So the regressive issue is more complex. Moreover, avoiding congestion pricing because of income distribution effects is a bad way to deal with inequality issues.
It would not be effective to charge employers since that requires keeping track of which company each driver works for, and whether their employees drive to work. It also ignores driving during congested times by shoppers. Otherwise, as someone commented, it generally does not matter whether employees or employers "pay" congestion taxes since the incidence of a tax would be the same.
I do not know if downtown property would increase or decrease in value. For example, the number of shoppers going downtown could increase if the reduction in travel times by car makes shopping in downtown areas more attractive.