I'm a grad student in mechanical engineering, specializing in fluid mechanics, my research nowadays is strictly in artifical heart pumps (Ventricle Assist Devices, or VADs). So, I guess me and Polite Scott could have some nifty in-depth discussions re: Tony Stark here, and his long history (and future) of heart problems and the devices he uses to keep him upright (when he's not busy knocking himself down with booze, that is).
Engineering is, and should be portrayed as more than that. It isn't just that you have an idea and build it; yes, that gross oversimplification can work a lot of times in fiction, but it doesn't really do the profession justice. There's also questions of ethics (something that almost never comes up, and probably should), of usability (like, ok, Tony built the armor, but the only problem Rhodey had with it was with some the mind hook up? Not the fact that he was taller and has generally been depicted as having a much more muscular frame than Stark? What the hell?), of safety and redundancy engineering, and of standards for the public and for others. That's a lot, and I think it could make for some really cool stories. But, that I'll leave for future days.