Your priorities are very different from mine and you appear to believe that we could create a single-payer system in this country which would (1) be satisfactory to most citizens and (2) cost half as much as our aggregate spending today. I don't believe that is a possibility in this country, though you appear to accept it as an undeniable fact.
Our current spending on existing government payment health care programs (Medicare, Medicaid and Military) is already vastly higher than what was forecast just a few years ago, and there is no good reason to believe that extending its reach will correct that already existing problem. An additional dose of the same poision is generally not a good treatment. Moreover each of these programs is already highly politicized with well organized lobbying and self-interest groups already in place orchestrating the activities of politicians all too willing to play to their particular grandstands with public money, whenever it is to their advantage. One can readily see that analogous systems in the UK and Canada are fairly constant political issues in their own political discourse, and they, in my view, are far more likely, given their traditions, than are we to make such a public syatem work.
I am Medicare eligible, though I still work full time. One simply can't easily find a medical praticioner here in the San Francisco Area who will accept a Medicare patient. As a result Medicare is (theoretically at least) my secondary insurance. I pay about $7,800 annually in Medicare employment and part B taxes, and doubt that I have ever collected more than $1,000 in any year in benefits from it. Why should I welcome more of that?
I think you are indulging your personal fantasies about a non-existent public health care system, supposing that it will have none of the already existing defects of existing ones in this country and will, at the same time cost far less and deliver better service - in the hands of Nancy Pelosi (whose Father bled the city of Baltimore MD white while his political machine ran the place) and other like-minded "progresseives" who are very sure that they alone know what is good for the rest of us. I don't agree.