(except for the obvious) The Best Idea Marvel Ever Had Was...

[Surf]

Jim Shooter as EIC. The 80s books flourished under him and getting licences for GI Joe and the Transformers hooked kids like me in the 80s.

[DrNewGod]

I'd say the villain swapping that began as early as the Avengers first tangle with Sub-Mariner. You saw a lot more of that kind of trading later. This went beyond team titles, or having characters guest in each others' titles or features. It gave a subtle richness to the notion that this was a single environment, where the events of one comic had meaning for another.

[Kirby101]

Continuity and a truely shared Universe. That books were part of a long ongoing story. And the emotional life of the characters mattered as much as the adventures.

[Ptrvc]

The Hulk. If you think about it, the Hulk was Stan Lee taking the Captain Marvel concept that had sold like gangbusters a couple decades earlier and updating it for the older, angstier audience of the Silver and Bronze Ages. Instead of a little kid transforming into a personification of righteousness, you had a man transforming into a personification of pent-up anger. The concept spawned a television series that was arguably Marvel's most successful venture outside of comics until the MCU.

To be fair it took them a while to come up with the rage connection. Once they did though...

[616MarvelYear is LeapYear]

The Origin of The New Mutants

[your_name_here]

More modern great ideas...

Annihilation and the revitalisation of the cosmic side of the MU.
Kamala Khan.

[Zero Hunter]

The Hulk. If you think about it, the Hulk was Stan Lee taking the Captain Marvel concept that had sold like gangbusters a couple decades earlier and updating it for the older, angstier audience of the Silver and Bronze Ages. Instead of a little kid transforming into a personification of righteousness, you had a man transforming into a personification of pent-up anger. The concept spawned a television series that was arguably Marvel's most successful venture outside of comics until the MCU.

I think your reading to much into this. The original Hulk was clearly a take on Doctor Jekyll and Mister Hyde. A meek scientist who turns into a brutish angry monster. I don't think Captain Marvel was even an after thought in Stans head when he came up with the Hulk.

[Blind Wedjat]

Stan Lee and Jack Kirby creating Black Panther and Wakanda as an anti-colonialist fantasy during the era of the Decolonisation of Africa.

[Hybrid]

The Origin of The New Mutants

New Mutants was definitely a great idea, for multiple reasons:

• It was the first X-Men spin-off title ever, and had proved that mutants can be a brand outside of just X-Men. This was basically ground zero for having an entire line of X-books as opposed to one X-Men title, paving the way for X-Factor, Excalibur, X-Force and so on.
• It was also a place to be experimental with different styles, like the trippy and abstract art of Bill Sienkiewicz that made it stand out.
• Furthermore, it helped to connect X-Men to other genres. Whereas the main X-Men book was based primarily on science fiction with heavy soap opera elements, New Mutants brought us horror and fantasy, with mystical beings, lost civilizations, demonic realms, and alternate futures being the flavor, and I believe that this proved that a mutant book can be as versatile as any other.
• Though unintended at the time, New Mutants towards the very end would give us Cable and Deadpool, which speaks for itself.

[Sutekh]

New Mutants was definitely a great idea, for multiple reasons:

• It was the first X-Men spin-off title ever, and had proved that mutants can be a brand outside of just X-Men. This was basically ground zero for having an entire line of X-books as opposed to one X-Men title, paving the way for X-Factor, Excalibur, X-Force and so on.
• It was also a place to be experimental with different styles, like the trippy and abstract art of Bill Sienkiewicz that made it stand out.
• Furthermore, it helped to connect X-Men to other genres. Whereas the main X-Men book was based primarily on science fiction with heavy soap opera elements, New Mutants brought us horror and fantasy, with mystical beings, lost civilizations, demonic realms, and alternate futures being the flavor, and I believe that this proved that a mutant book can be as versatile as any other.
• Though unintended at the time, New Mutants towards the very end would give us Cable and Deadpool, which speaks for itself.

Some of my favorite features of the New Mutants;

A) Very diverse, for the time, which followed the precedent set by the 'All-New X-Men.'
B) In a genre where teams generally are four to six dudes and a token woman, or, as Image joked around, 'the standard new team format of one established loner, two veteran heroes, and a couple of bimbos nobody's ever heard of before,' it was a team with more ladies then gents!
C) The team had relatively low power levels, as befitting their status, and no one of them was a 'do anything' sort of character with powers useful for offense *and* defense *and* utility/transport. They seemed designed to require a team, and function best covering for each other, as opposed to some popular mutants who kind of do it all and don't really need a team, much. Dani and Karma, in particular, had a tiny subset of the power even a bargain basement telepath has, and managed to make it work.

[ERON]

I think your reading to much into this. The original Hulk was clearly a take on Doctor Jekyll and Mister Hyde. A meek scientist who turns into a brutish angry monster. I don't think Captain Marvel was even an after thought in Stans head when he came up with the Hulk.

I didn't mean to insinuate that Stan consciously modeled the Hulk after Captain Marvel; just that he was tapping into a similar archetype.