Iron Man was in various stages of production for a very long time before Marvel managed to finally to get the movie into production, so a number of different versions of the script have been in existence over the years (there's even one where Tony Stark would have had a talking toaster and been unable to fly). The strangest involved Tony's father Howard. In an early draft, Howard was going to be revealed as still being alive. He then would have served as the movie's main villain... War Machine?! That obviously would have been a major change to the source material, but Iron Man still implemented at least part of this idea. That was evident from the father/son dynamic between Tony and Obidiah Stane, though his Iron Monger moniker was obviously taken from the comics and War Machine was only hinted at. Marvel did however switch the hero/villain dynamic of an armoured character in Iron Man 3 when the villainous Iron Patriot became a hero when piloted by Rhodey.