What should we replace Obamacare with? Perhaps we should try freedom:The biggest problems with Obamacare are, from my perspective, these:
1. The freedom to choose inexpensive insurance free of government dictates.
2. The freedom to save unlimited amounts in a health savings account.
3. The freedom to buy insurance across state lines.
4. The freedom for all individuals to join together in voluntary associations to gain the leverage of being part of a large insurance pool.
1) It makes my health everyone else's business, which means that everyone else in theory has an interest in telling me how to live.
2) It distorts the market towards worse kinds of jobs, especially at the lower end. The result is to increase poverty and the hardship of life for working Americans.
3) The mandate is unconstitutional, SCOTUS notwithstanding.
It's unclear from the details in the wild whether Rand Paul's plan fixes those three things, although it sounds like he probably is gunning for the mandate.
According to Paul's Twitter account, which I suppose is how we do governance now, Trump is 100% on board with the plan.