Iron Man ultimately faces the problem that he can't hurt Doom. Unless Tony has something in his arsenal that either resembles the surfers energy attack or Johnny's supernova then it's looking pretty grim from my perspective. His best hope would be to try and bfr Doom into a ocean or something similar. We also lack information on which armor Tony is wearing. If it's one of the two from Avengers it can be debated that Doom's lightning will just increase Tony's power, while if it's one of the armors from IM3, I think it's fair to assume that the lightning will at the very least do significant damage.
The armors themselves were more fodder than the Extremis soldiers. Don't ignore that Tony was extremely insomniatic and full of anxiety for the entirety of the time he was creating them. But we see how tough his actual armors are like War Machine and Mark 41(I think that's the Avengers suit)
And yeah, Doom wasn't all that strong. The first time he took Thing's strength and any actual force behind his blows seemed to be a taser effect from releasing electricity whenever he hit you.
You mean to tell me that he used a different, weaker alloy to forge the armors? Where's your proof for this idea? Not to mention that the process of creating the armors was automated.
Lol, what is this crap? Doom was going toe-to-toe with the Thing as you noted in your post. What you didn't note was that Ben had enough strength to lift the London Eye in the 2nd movie. Which makes Doom going toe-to-toe with him an impressive h2h/strength feat.
Not to mention Doom's insane energy resistance/durability. Tanking a supernova that can kill all the life on Earth is by no means a small feat either.
Gender: Male Location: 4th Street Underpass, Manhattan
Besides maybe the tri-beam, IDK WTF Stark has in his arsenal to take down Doom. The hits from Thing and near-supernova level heat Doom has withstood is beyond anything Stark has ever deployed.
Also, Doom is smarter since he was wielding cosmic energy-siphoning weapons and tachyon generators, whereas Stark was working hard just to build a new element.