Not allowing an insurance company to negotiate for the price of a drug or service is precisely why medicare and medicaid have ballooned up to 39% of US federal spending while not even approaching "universal" coverage.
I'm possibly misunderstanding you, but you seem to be implying there would be no negotiation in the system I described. I never said that. You as a patient would in fact be much more empowered to negotiate with those who provide you services, since you would actually know the actual costs available in the market.
However, if your point is that the current system would also be improved by the tiny change of allowing medicare to negotiate prices without any of my other ideal changes, then yes I agree that would be a change for the better.
However, if your point is that the current system would also be improved by the tiny change of allowing medicare to negotiate prices without any of my other ideal changes, then yes I agree that would be a change for the better.