Indeed it is a very scary word. So stop using it.
There seems to be tremendous focus on how precisely individuals and businesses would interact with some grand health care plan, of how exactly to get them to sign up. To me that part's rather easy. Send everyone a membership card in the mail! All done.
Even recognizing the political realities of the situation, it seems that the way to sign everyone up is to... sign everyone up. Instead of having "mandates" requiring that people sign up to some plan, just sign them up. Instead of mandating that they pay their premiums every month, just pay for it out of general tax revenues (adding a new payroll tax or raising top marginal rates or whatever to do so).
Even if insurance companies are in still in the mix I see no reason for people to have to proactively sign up for some plan they may or may not be able to afford.