Several Medicare for All proposals are on the table. I intuitively liked one alternative, a Medicare buy-in for those age 50 to 64; moving towards a well-functioning single payer system and more incremental than Medicare for All.
Medicare for All
The Mercatus Center, alternately characterized as a libertarian think-tank or a “Koch [brothers] backed think tank” released a financial analysis of Senator Sanders' Medicare for All Act, the only single-payer legislation currently proposed.