I would like there to be a baseline level that everyone has access to. What that baseline should be is not something we will all agree on, and I would likely set it lower than you, not because I want poor people to get worse coverage but because there are costs (including opportunity costs) to raising that baseline level. And in fact, we already have a baseline. It's well below what you want, but it's there.
So I want a baseline, I'd probably set it lower than you would, but I'd also like it to be possible for almost everyone to purchase care above that baseline. I'm not actually a heartless bastard, I'm just a regular bastard.
So I don't see where that differs from the position in Britain. Except that you seem to want to set the standard level of care lower for US citizens (who are paying lots of money) than it is for British citizens (who are getting a pretty good bargain when you get down to it).
I'm intrigued to know why you want to set the baseline level of care lower than it is in Britain (which is about where I'd imagine Architect would probably set it). What costs are we incurring by providing the service we do, "including opportunity costs"?
Medical insurance is not especially expensive here, and for a reason. The insurers know that they are not going to be required to pay out for any emergency treatment, or for ordinary routine GP appointments. The insurance is generally only invoked for non-emergency consultant appointments and subsequent treatments.
Nevertheless, not many people actually buy their own health insurance. The reason is that all the insurance buys you is a private room in a swanky hospital, and the procedure done at a time convenient to you (yes, often sooner). For most people, it doesn't seem worth it. The idea of buying insurance to pay for procedures that are not clinically necessary, such as extra MRI scans and so on, doesn't enter anyone's head. I suspect that even in the USA, if a similar system were in force, most people would sooner or later come to the conclusion that they'd rather keep their money in their pockets than pay for unnecessary tests and unnecessarily expensive drugs.
The other option is to pay for a procedure to be done privately out of your own savings. My mother did this when (for very particular reasons) she was going to have to wait over a year for cataract surgery. My mother is a clergyman's widow on a small church pension. Nevertheless she had the £3,500 it was going to cost, and she decided to spend her money. Was it worth it for that 13 months of better sight? Who knows. But she had the freedom to choose.
This is how it actually works, in practice. I'm really quite hazy about how your proposal would work in practice.
Rolfe.