I think we're forgetting that Doom is a LOT older or should be chronologically because he went back in time to the Library with Molecule Man and was there for....25 years? Now he probably de-aged himself as God Emperor, but his mind still experienced those events. He has to be pushing 80.
I think Dr. Doom is like 500 years old since he time traveled into the past to learn magic and "waited" to reach the present day.
If you really want to go crazy, factor in Dr. Strange's age. He went to med school, then became a surgeon, then became a famous surgeon. Then he had his accident. Then he spent years searching for cures (spending his fortune along the way). Then he became a bum on skid row, then he made his way to Kamar Taj. So, even assuming he is a genius, he had to have been in his mid to late 30s by the time he got to Kamar Taj.
Now some writers like to write that magic powers were just bestowed on him, like he was bitten by a radioactive amulet, but the original story is that he studied and studied and studied at the feet of teh Ancient One. There is some text that just being in Kamar Taj slows one's aging, so he didn't appear to physically age as much, but figure ten years of study to master the mystic arts and be sent back to NY. And then he stopped aging at all (during Englehart's run). I figure that he, arguably, could be in his late 50s or early 60s--and just not look it.
Roger Stern used to occasionally have a character make a comment to the effect that they remember the great surgeon Stephen Strange, but then decide that Doc could not be him because he looked much too young. This was Stern acknowledging the age-retarding bits of Strange's life. As always, Stern understood the character better than most.
"Age is not defined by years, but by regrets...I'm an old man now." --Fighting Yank, "Project Superpowers"
I choose to subscribe to the Franklin is afraid his power and doesn't want to grow up theory so he is altering reality to keep anyone from aging. Some people who have read much more FF than me have actually put a lot of work into gathering evidence for this in regards to things that have happened with Franklin. I don't think Marvel is really doing this as that would require a lot of planning and forethought but its a nice theory so you can stop thinking about how little sense the Marvel timeline makes.
I hope that myself and the others putting the time into this realize theirs is a minority opinion. The fact that Marvel is not going to, or even is capable of, locking in an encompassing timeline makes this thread sheer speculation. That's cool.
The advantages and fun of a thread like this are that we can launch our theories and our jokes.
I like this. We have to all remember, sorry, but as Elton once sang "Comic book characters never grow old".
My head canon always says that Sue is around or not quite 10 years younger than Reed and Ben. She is always at least 5 years older, but possibly a few more than that. But not 10. The range of ages for the FF should be sorta mid / late '20s to early / mid '40s. (I choose to forget that after SW they were gone several years, 5 even, on their own - - or the effects of the Skrull age ray being reversed (FF early # 200s) gave the boost that makes it negligent.)
I seem to recall Johnny needing to secretly get his high school diploma when the FF lost their powers after a battle with the Frightful Four. I believe Johnny started college around the first time Galactus showed up. It would make sense that Johnny may have gotten behind in high school being part of the FF.
The O5 aging compared to Peter & Johnny has always bugged the hell out of me. I always blamed Wolverine & Kitty for that, lol. I still consider Emma being at least 5 years older than Scott during their relationship.
Tony Stark was always a grown-ass man to me, but this is the first I've heard of him being 40. In Busiek I trust! The RDJ casting makes even more sense!
The problem with the X-Men is that they keep introducing younger generations of mutants every 5 years or so (instead of more contemporaries to mainstays who trained themselves without the need of Xavier), who ultimately become cannon fodder/wallflowers, but also ages up the previous generations. Kitty & the New Mutants/X-Force should never exceed past 20. The surviving members of Generation X are grown now.
Yet somehow, Franklin had to go on hiatus in order to show a little age.