I was going to mention the original Human Torch (1939) had a classic “monster turned hero” story arc. I can’t remember if the android was intended to burst into flame when unveiled, but he was definitely feared when it happened.
He wasn't intended to flame on and was an unintentional menace whose ignorance briefly exploited by criminals in his first story (arc isn't the right word for it, it was one issue), but that was fixed by the end of his first appearance and he was explicitly a hero from then on, even getting his sidekick Toro in his second issue of Marvel Mystery Comics. His "monster" period was an eyeblink in a fairly long career.
And The Whizzer was battling personal demons- namely alcoholism- in the early 1940s. That’s decades before Iron Man had his own bout with that affliction.
No, I'm afraid not. That's retcon from much, much later on, like most of his "history" has become. He was a fairly typical Golden Age hero in the actual 1940s (right down to briefly having a racist caricature "comedy sidekick" in the form of Slow Motion Jones) and he fell out of print for about a quarter of a century from 1946 to a revival in the 1970s. Marvel's dragged the Whizzer out of obscurity so many times over the years it's kind of amazing, retconning him into multiple superteams that never existed in the 40s, tying him to modern characters and stories via multiple time-travel plots, and generally building up his brief early career to the point where his retconned activity massively outweighs his adventures in chronological publishing history.
In short, his history's a mess and you have to go back and check when and where character elements and related events were actually published on everything regardless of the date in the story itself - or where in the Marvel Fandom timeline a given thing falls, since they've blithely integrated all the retcons there. He was never married in the actual Golden Age books, the WW2 era groups he was on didn't exist during the War, etc. And that complicates post-revival stuff even farther, since his kids (Nuklo and the stillborn one he mistook Wanda and Pietro for) are the product of a retconned relationship between him and Miss America. The "drinking problem" stuff you're citing stems from Bronze Age events involving his retconned kid Nuklo, and I'm fairly sure it was actually added to his timeline even later than Iron Man's 1979 Demon In A Bottle run.
If there's a bright point in all the retcons Whizzer has been put through, Marvel seems to have made a half-hearted attempt to redeem Slow Motion Jones by retconning him into a speedster hero in his own right and his Golden Age portrayal into "propaganda" for the public. I'd be a lot more impressed if that attempt had included any real effort to portray him as a hero in action, but All-Star Winners Squad didn't exactly get a long run and we spend a lot of time with Jones as an old man on a walker with bladder problems.
Tying this into the meta-Republic campaign idea, if there's a lesson to be learned from Marvel's retcons its to Not Do That. Don't introduce time-travel or retroactively change past events in your game or you're going to wind up with this kind of mess.