This is a great question, and I am sure that there will be many different opinions. I would say that the most significant phase in public policymaking (as it relates to healthcare) is making something theoretical or even just a good idea into law. It takes an inordinate amount of time for something to become law.
It took President Obama a very long time to pass his healthcare reform.
On Feb. 24, 2009, Obama addressed Congress and stated that health care reform cannot wait. On September 29, 2009, the senate rejected two amendments to this bill. So there was more stalling. On March 23, 2010 Obama finally signed the new health care reform. All seemed well until, on August 12, 2011, the 11th Circuit Court of Appeals ruled that parts of the law were unconstitutional. In the end, it all worked out, but the politics involved slowed everything down considerably.
Now that we have "Obamacare," there are more challenges. However, the challenges of getting the reform passed into law was the hardest and most significant part. That we are on the right track was confirmed when Obama spent over five minutes of his speech at the State of the Union talking about his new healthcare reform.