Why not let Obamacare run for 2 years and let Americans be the judge at the polls in 2016?

Because once something this massive starts it is almost impossible to undo.

Because it was initially a republican plan. When Obama adopted it, the republicans washed their hands of it, correctly assuming republican voters wouldn't know that they have initially come up with it. It isn't a perfect plan, but it's better than nothing. Some red states aren't doing it. If it goes into effect, and the blue states that are have more people covered, and realize a savings, it will make the republicans look bad.

Not to mention they have a pathological fear of Obama succeeding at anything.

If it works the republicans will never get over it.
As a party they will be washed up.

because Americans will LOVE it and the Republicans will be proven to be liars.

Great idea! I mean already without it being in full effect many companies have cut the hours of their part time employees from 32-36 hours to 24-28 hours so they don't qualify. Those families who were struggling to provide are now struggling even more. More than 60% of our medical professionals are at retirement age ,Nurses and Doctors, they have already stated for the vast majority they will retire if this is fully implemented, many already have. So who is going to treat those sick or injured people? SO you have a government that is going to subsidize the health-care with tax dollars that are not coming in and doctors and nurses retiring, so no one to do the surgery or treat the patients. The cost going up in 80%+ of the States and no medical professionals and more financial debt on the good ole USA.

Do we really need two years?

Because it is hard to unbake a cake, even a sh!t cake that is Obamacare.

Because within 2 years **** can be added to it to make it irreversible. Obama has already shown he has no respect for laws and changes them as he sees fit

I am not sure I understand your question, but Obama cannot run for President again, because he was twice elected to the office, and is therefore ineligible pursuant to the Twenty-Second Amendment.

EDIT:

I misread your question. The Republicans do not want Obamacare to get started, because they know people will like it, and that the Republicans have been lying to them, trying to protect their greedy corporatist sponsors.

Because we don't run an "all or nothing" government.
The representatives of each state are not required to roll over and vote "Yes" to everything the winning side wants and never have been expected to.

Why would you suggest such a thing? Is it really the sort of government you want? A total autocracy by President?