The birth of Vader felt like a rushed CG fest to me. It is like Palps had an instant Vader maker lying around for just such an occasion. Throw in the half dead, charred body of a fallen comrade and presto! Out pops your very own Sith Lord! I just didn't like how he spends a few minutes on the table as a bunch of droids throw artificial appendages on him, and slip a leather suit right onto his freshly burnt and still melty skin. Then he stands up and everything is fine. I would have imagined months of rebuilding with some of the republics finest physicians.
Ha! This made me laugh. Yeah, it is kinda implausible, and the scene is probably meant to represent the passage of a LOT of time. Unfortunately, George got to the last half of Episode III and suddenly realized he still had to set up a whole bunch of stuff for the OT.
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I've got problems with how Episode III leads into the OT-- but "implausible medicine" isn't one of them. The Sith Lord isn't the prosthetic suit-- it's the man inside. Where did you get the "months of rebuilding" idea? Jedi Med School? Luke got a new hand like they had one waiting on the shelf for him. The way it's established in the movies-- their medicine either fixes people in a few minutes --or can't work at all. These guys fly from one star to the next as easily as we drive to the market. The one constant in Star Wars is that their technology is way beyond ours.
So, yeah-- it would be as easy as slapping some legs and arms on the body, making sure it can breathe, and then waking the poor bastard up. It could've been done nicer, but Palpatine is sadistic. "You killed your wife, dude." "No-o-o-o!"