I'm in an optimistic mood today, so let's begin by assuming that ObamaCare is dead, and that the Republicans manage to achieve a majority in the House (control of the Senate still seems unlikely, even to Optimistic Mario). OK?
The first thing that the new Republican Majority needs to do is to neuter future health care reform. We know that the American people are against a government takeover of healthcare, and show no signs of changing their minds, yet this doesn't stop the Democrats from periodically attempting to put such a takeover in place. This time they nearly succeeded; it's true that it wouldn't be a full takeover right away, but it's easy to see where Obama's road would have taken us, particularly if he had been able to blitz the original bill through before the August recess.
How is it, then, the the Democrats have gotten so good at convincing America to accept their plans even though we oppose the end result? The trick is that they use real issues, things that America actually wants to change, and misleadingly set up their bill as the solution to the problem. If we choose to ignore those issues now that ObamaCare is dead (arguendo), we will just be setting ourselves up for future near-disasters, not to mention proving that Republicans don't care about governing.
The Republican Majority's first action upon taking power, therefore, needs to be real healthcare reform. Things like rescission strike people as wrong for good reason: they are wrong. If the Democrats (hopefully) fail to pass their bill, we need to make sure that our first priority is to rip the good pieces (however few) out of that bill as pass them separately. There may need to be a few tweaks in the language, but I imagine that most could be passed word for word from the Democrat bill. More importantly, we need to campaign on this platform; elect Republicans and you'll get what you wanted to get from the Democrats, minus the radical agenda.
We should never make the mistake of thinking that just because something was proposed as part of a socialist plot, it is automatically without merit. Yet I fear that we make this error far too often, and provide the Democrats with the opportunity to exploit these blind spots and press their agenda. Good governance means never providing the opposition the chance to outflank you.
Taking this strategy would be good politics (campaigning on it might even be good to boost the size of the majority) and good policy. As a side benefit, we would neuter the prospects for a future government healthcare takeover by denying the Democrats many of the openings they need to get their radical feet in the door (or hands in your pocket, if you prefer).