Start a business that does it right. If you can get past the regulators and such, and there are enough rational customers, you'd do better than everyone else, and they'd start copying you.

Well, good luck getting past regulators in a profession that operates as a self-regulating guild!

In my opinion, the only mechanism of competition that could conceivably ameliorate the systematic problems of medicine is the international medical tourism. However, I'm far from certain that free competition has much potential for preventing medicine from drifting away from reality, considering how much people are prone to biased and even outright magical thinking on this subject, even when all the incentives to get things right are in place.