Obamacare, like almost everything the government is in charge of, is undoubtedly a disaster and needs to be repealed. Why should it be replaced with anything? We already have an extensive Medicaid program, which was supposedly designed to provide a safety net for those unable to afford insurance. Like most if not all government programs, it is rife with fraud and abuses.
Medicare is another disaster. The majority of people think this is a free government program that pays 80% of everything. Nothing could be farther from the truth. Seniors pay for Medicare, and Medicare pays for 80% of what Medicare thinks you should have been billed.