In reality, at least in the US today, I don't trust our government to do this right. They're already way top friendly with the medical industry and have absolutely no idea what it means to plan finances. They waste a ton of tax dollars as-is and have no answer as to why we need taxes when they can literally create trillions in new money every year.
On the medical side, my only caveat would be that I'd want a system that offers more than just modern, western medicine. Anyone that believes strongly in alternstive medicines should have their care covered as well, I'm not sure how that works in other countries that have socialized medical care today.