Having 10 points chock-full of wonky statistics is a perfect way to lose an argument. Even if you can remember all that, in any debate you'll get into a tit-for-tat, and the undecided get confused or scared... To them, "no change" is better than something that sounds confusing or scary.
All we need are 3 simple points; a robust public plan is a matter of responsibility, competitiveness and morality.
Responsibility
The public plan will bring uninsured people into the system; making them responsible for their health care choices. Right now, the rest of us are paying to treat the uninsured. This is unfair to the insured majority. A public plan will collect some money from the currently uninsured, giving them more personal responsibility. It will also make it more likely for people to seek treatment for their issues before they become expensive emergencies – again, fostering responsibility for one’s own health care.
Competitiveness
The US is in competition with other industrialized countries for businesses and highly-skilled workers. Businesses that decide to locate in the US have to pay an added burden of health insurance for their workers. This makes the US less attractive & un-competitive on the world stage. The US still has other advantages, but those are more and more being squelched by the high cost of health care.
Morality
Imagine this: A person shows up at an emergency room having kidney failure. This person has no insurance... they might not even be a US citizen. Should the hospital turn them away? Let them die on the sidewalk? No, of course they treat them... and the rest of us pay for it with higher fees. Essentially, this is the situation we have today. It’s a public plan, but a stupid, unfair and expensive one. We have a moral obligation to treat the sick; let's act like we mean it.
Summarized in one paragraph:
We are already paying for the uninsured; we have a moral obligation to do so. A robust public plan will make those people more financially responsible for their own health care, and encourage them to seek treatment prior to an emergency. The United States is in international competition for businesses and people. A robust public health plan will make the US a more attractive place to live & do business.
Fear
The one thing I might add is a comment on fear. People fear what they don’t understand. If you make the case difficult to understand, people will fear it. Explain that the entire industrialized world has decided to have some type of public health system and/or insurance; it is nothing to fear. There are not hordes of people dropping dead all around the world. NOBODY in any other country would exchange their system for ours. If you asked the average Swede/Brit/Canadian/German/Japanese if they’d like to trade their system for ours, they’d simply laugh at you.
The few Republicans I've heard who actually support a public plan (or even a single-payer system) have agreed with these arguments, and cited them as reasons for their decision.
I know people mean well when they quote statistics about the salaries of health care executives or the number of uninsured... those things get me riled-up too! But, they don't help win-over the undecided. It has to be simple. I wish I could boil it down to one point. Perhaps to one sentence or one phrase. Maybe someone can do better than me? Good luck out there!