You know how animated series get to pick and choose and create these "perfect" versions of their respective universes using ideas from decades worth of stories? I had a notion to do something similar with the Marvel Universe, taking the idea of heroes aging in real-time and applying the idea of how different eras affected the writing of different characters, and creating a Marvel "timeline" that starts in the 1940s and extends into 2010. It's a skeleton at best, but I kind of like the idea, maybe as a backdrop for a Marvel RPG or something. So here it is:
The heroic age begins in the late 1930s as heroes emerge to face the growing Nazi war machine. Namor the Sub-Mariner reveals the existence of Atlantis, and joins the American super-soldier Captain America and the American super-android Human Torch, alongside the British Union Jack and Spitfire, as the Invaders. The Germans, desperate for weapons of their own, summon the Norse god Thor, who quickly realizes he's on the wrong side and joins the Invaders. However, the use of Nazi sorcery results in a bit of a stalemate with Allied super-powers, and the end result is that the war is still won by human soldiers and bravery, and the development of the atomic bomb is still necessary to end the war. Captain America is lost, frozen in ice, and Thor returns to Asgard.
The bridge between the Golden Age and the Atomic Age of heroes. A group of government-affiliated heroes known as the Agents of Atlas are the primary American heroes, although there are "greaser" heroes operating on the streets as well, the precursors to urban vigilantes like Spider-Man, Punisher and Moon Knight. In addition, war hero Sergeant Nick Fury becomes a Colonel and heads up the newly-created SHIELD (Supreme Headquarters International Espionage Law Enforcement Division). They begin keeping tabs on superheroes and supervillains alike.
The Atomic Age truly begins when the Fantastic Four steal a rocket in an attempt to beat the Russians to the moon and are bombarded with cosmic rays, returning as the first American heroes with public identities. Shortly thereafter, atomic accidents create two new heroes who are often mistaken for villains in Spider-Man and the Hulk. And background radiation from nuclear testing has resulted in the birth of mutants, including the original X-Men and the original Brotherhood of Evil Mutants, who begin a very public war over the future of mutant-kind and how it will interact with humankind. In the late '60s, a trip to Vietnam results in Tony Stark creating his Iron Man armor, and he returns home to help found the Avengers, alongside a returned Captain America and Thor and new science heroes Ant-Man and the Wasp. The Hulk is an early ally, but proves unstable and leaves the team before the '60s are over to roam the country.
The Revolutionary Age, when many social conventions were being shaken and tested. On the streets of New York, increases in street crime, organized by the Maggia and the Kingpin, are met with resistance from urban vigilantes like Daredevil, Punisher and Power Man & Iron Fist. Meanwhile, an Eastern influence begins with the birth of Doctor Strange and the war between Shang-Chi and his father Fu Manchu. There's also a general increase in "weirdness" and counter-culture, as evidenced by the rise of superteams like The Defenders and the All-New, All-Different X-Men, who represent a more international than American team. The Avengers and Fantastic Four continue their adventures, although they are increasingly out in space, dealing with cosmic problems like the Kree-Skrull War or Adam Warlock and Captain Marvel battling Thanos and the Magus. Meanwhile, a new wave of feminist heroes emerges with Jewel (Jessica Jones), Spider-Woman, Ms. Marvel and She-Hulk. The Avengers roster expands to include Wonder Man, Vision & Scarlet Witch and the Falcon.
The Legacy Age begins, as heroes from the Atomic and Revolutionary age begin to age and retire or die. Captain Marvel is the first notable hero, dying very publicly of cancer. Phoenix dies soon after, sacrificing herself to save the universe. Captain America, having now reached his 50s, begins training Jim Wilson, a.k.a. the Falcon, to take over as the new Captain America, and recruits many new Avengers, including the new Captain Marvel (Monica Rambeau), Black Knight (Dane Whitman), Hercules and Tigra. Tony Stark passes on the Iron Man identity to the son of his pilot and best friend, Jim "Rhodey" Rhodes Jr., who joins the new team as well. On the streets of New York, Moon Knight joins Daredevil and the Punisher in their fight against the Kingpin and his ilk, while a sonic-powered mutant named Dazzler makes big headlines as the first mutant with a public identity (and multi-million dollar recording career). The X-Men recruit a new class of students, the New Mutants, to their academy, as several of their number retire to teaching careers at the school. During the mid-'80s, the Secret Wars take place, and many older heroes are killed in battle against their long-time foes, resulting in the new "legacy" heroes having to face of against the resurgent Thanos and his Infinity Gauntlet.
The Dark Age begins with the death of Spider-Man. With so many of the established heroes gone or retired, a vacuum forms for newer, darker heroes with darker codes of justice. The New Warriors step up as a young hero team to replace what they see as the "establishment" Avengers and are embraced by a youth culture influenced by grunge rock and nihilism. New strange heroes like Darkhawk and Sleepwalker emerge. The X-Men and New Mutants find themselves divided between Xavier's dream and Magneto's, and a new militant leader named Cable turns much of the New Mutants into X-Force, battling more dangerous foes like the deadly mercenary Deadpool, the deadly Apocalypse and the resurrected Brotherhood of Evil Mutants, now headed by the psychotic son of Charles Xavier, Legion. Legion's time manipulations result in the creation of the alternate universe Age of Apocalypse, which results in the death of several mutants, including founding X-Men Angel, transformed into Apocalypse's Archangel of Death. Meanwhile, the Avengers are disbanded, scattering to different parts of the country to fight crime in their own ways. Stark Technologies begins a focus on improving techology for everyone, which includes a major Iron Man upgrade. Captain America begins a network dedicated to creating a sort of national Peace Corps.
The New Age begins, as new incarnations of familiar teams are formed. The New X-Men are centered around the X-Corporation, an international mutant advocacy group for the growing population of mutants. It's membership includes former X-Force, X-Men and New Mutants members, as well as numerous new mutants, and it's board includes the surviving original X-Men: Cyclops, Iceman and Beast. They also maintain the Xavier Academy in Westchester and open the Grey-Worthington School in San Francisco as havens for mutants. After disbanding in the late '90s, the Avengers are reformed when a massive multi-super-prison break calls for their return. The team is organized by the son of Nick Fury and headed up by Power Man (the son of Luke Cage and '70s heroine Jewel), and includes a new Spider-Man (Miles Morales), a new Iron Man (Tony Stark's grandson), Wolverine (in a show of mutant solidarity with these new heroes), a new Captain America (the daughter of Winter Soldier & Black Widow) and Thor, newly returned from Asgard. They also create the Avengers Academy, a school on the west coast designed to bring new heroes into the Avengers fold in the future. In the shadows of Los Angeles, a new group of teen heroes, The Runaways, are formed when they discover that their parents are super-villains, and in deep space, Thanos rises again to find himself confronted by the Guardians of the Galaxy.
And for further spiff-balling, here are the potential titles that would be published during these years. There would probably be more:
(*) indicates a book that continues from the previous decade
The Invaders (1939)
Agents of Atlas (1950)
Greaser Hero (1952)
Nick Fury and the Agents of SHIELD (1953)
Amazing Spider-Man (1961)
Incredible Hulk (1962)
Fantastic Four (1963)
The X-Men (1964)
Iron Man (1965)
The Avengers (1966)
The Mean Streets (Daredevil, Punisher, Power Man & Iron Fist) (1970)
The Defenders (1971)
The Uncanny X-Men (1972)
Doctor Strange (1973)
Shang-Chi, Master of Kung-Fu (1974)
*Incredible Hulk (Ends 1978)
The Death of Captain Marvel (GN) (1980)
The Death of Phoenix (GN) (1982)
Captain America (1981)
New Mutants (1984)
Power Man & Iron Fist (1985)
Secret Wars (LS) (1986)
Infinity Gauntlet (LS) (1989)
*The Mean Steets (Punisher, Moon Knight, Daredevil)
*The Uncanny X-Men
The Death of Spider-Man (GN) (1991)
New Warriors (1992-1999)
Age of Apocalypse (LS) (1994)
Avengers Disassembled (LS) (1995)
Captain America Corps (1996-1999)
*The Mean Streets (Punisher, Moon Knight, Daredevil, Darkhawk) (Ends 1999)
*Doctor Strange & Sleepwalker (Ends 1999)
*The Uncanny X-Men (Ends 1999)
*Fantastic Four (Ends 1999)
*Iron Man (Ends 1999)
New X-Men (2000)
Mutant Academy (2000)
New Avengers (2000)
Avengers Academy (2000)
The Future Foundation (2000)
Stark Technologies (2000)
The Runaways (2001)
Guardians of the Galaxy (2002)