Marvel Comics is not the first, or even the second, comic book company to have a Captain Marvel, but it does have the longest continuous history of having one or another, or another hero published with that name. Now that DC has re-branded the character that originally held that name as "Shazam," and Marvel is scooping DC by scheduling the release of their Captain Marvel movie before DC's "Shazam!" movie, they have an opportunity to establish for the non-comic-reading movie going audience a strong identity for the name "Captain Marvel."
With that in mind, here are a few things that would serve their franchise well if Marvel were to include them in their first "Captain Marvel" movie:
1. Acknowledge their original Captain Marvel
Marvel's first Captain Marvel was Mar-Vell, a captain in the military of the alien Kree empire. He fought against and alongside such characters as Ronan, Thanos, Drax the Destroyer, and Gamora, who have already been established in the Marvel Cinematic Universe (MCU). Carol Danvers fell in love with him long before she became a superhero. In a battle between Mar-Vell and his rival, a Kree Colonel named Yonn-Rogg, an incident occurred that gave Carol Danvers the powers of Ms. Marvel, and his heroic example inspired her superhero career. It was upon his second death (no one ever only dies once in the comics) that she decided to take up the mantle of his name.
What ultimately made Mar-Vell unique was is dedication to preservation of life. Sure, that is, ostensibly, the job of all superheroes, but Mar-Vell had been given the job of "Protector of the Universe" and the power of "cosmic awareness" in his most famous storyline, written by Jim Starlin. He went from becoming an indomitable warrior to a "cosmic space hippie" who sought to solve conflict without battle where possible; a pacifist who used his powers for the cause of peace, rather than seeking out opportunities for conflict. This happened to also be the first major storyline that involved Thanos.
Marvel would be missing a great opportunity to pay tribute to this character if they did not work him into the story of Carol Danvers somehow.
2. Carol Danvers must have a defiant, independent streak in the face of old-school sexism
Carol Danvers defied her father and traditional gender roles by running away and joining the Air Force. She was head of security at Cape Kennedy, a job traditionally given to men. She was editor-in-chief of "Woman" Magazine, defying publisher J. Jonah Jameson's insistence on "traditional" female-targeted content. As a superhero she was introduced as "Ms. Marvel - the first feminist superhero." It was this sort of thing that defined her character.
Whereas Susan Storm (Invisible Girl/Woman) always stood by her man, and Janet Van Dyne (The Wasp) flitted through the world as a wealthy socialite, Carol Danvers faced the challenges of a male-dominated world head-on, and often beat them.
3. Captain Marvel's greatest challenge must be something she can't just hit
Captain Marvel is "Earth's Mightiest Hero." Her powers of energy absorption and projection, nigh-invincibility, and supersonic flight enable her to overcome almost any brute-force adversary.
But Carol Danvers has not succeeded in everything. She was fired from her jobs at Cape Kennedy and Woman Magazine. She became an alcoholic. She has never been able to keep a steady boyfriend. These are the kinds of problems faced by regular people every day. It's part of her character and what makes her so identifiable to her fans.
4. She must become popular with the public
Captain Marvel's character today has attracted a passionate following in the wake of the stories written by Kelly Sue deConnick. The Carol Corps was a spontaneous, grass-roots movement inspired by the character that has done everything from charitable deeds to inspiring the title of a recent 4-issue miniseries.
The other female superheroes in the MCU (Black Widow, Scarlet Witch) are either secretive or shy, and in the world of the MCU are not likely to attract fan followings and inspire people to good deeds and group action. Captain Marvel has the opportunity to be that person, that symbol, that public figure; a female Captain America.
One of the strongest moments in the recent comics was in "Captain Marvel" #17, when, as Captain Marvel was faced with the threat of destruction from someone with a grudge, the crowd of people surrounding her rose up shouting "I am Captain Marvel!" indicating their willingness to face the threat that she faced because they loved her and were inspired by her. This sort of thing hasn't been seen in a superhero movie since Sam Raimi's "Spider-Man," and deserves to be seen again.
5. The Kree must be involved
The Kree have been established in multiple streams of the MCU. Captain Marvel's powers came from Kree technology and DNA. 'Nuff said.
6. She must face Thanos
Captain Mar-Vell's greatest battles were against Thanos. Carol Danvers was inspired by Mar-Vell. Thanos is in the MCU. Need I say more?
Well, just because I want to say more...Mar-Vell was not killed by Thanos in the comics, but a slow lingering death from cancer is not terribly exciting cinematically. The rivalry between Mar-Vell and Yon-Rogg is probably too complex to include in the MCU, so using that as the origin of Carol Danvers' powers is unlikely. A satisfactory way to tie Mar-Vell, Danvers, and Thanos together would be for Mar-Vell to be killed defending Earth from Thanos, but somehow managing to pass his powers to Carol before he expires. Then Carol would be the hero who manages to defeat Thanos.
Honorable Mention: Include Monica Rambeau
Of all of Marvel's Captain Marvels, Monica Rambeau is the only one with no connection to any other. She is unique in the superhero genre by being a black woman. She is unique among black heroes for not having a name that starts with "Black," and among female heroes by neither having a name that states her gender (like Wonder Woman or Supergirl) nor being attached or related to a male character. That is a combination of uniqunesses that sets her apart from the entire superhero universe.
She was Marvel's first Captain Marvel after the first death of Mar-Vell. She was smart, capable, and led the Avengers for a time. Her name was changed to "Photon" after Marvel introduced a new Captain Marvel, Genis-Vell, Mar-Vell's son. It has since been changed to "Pulsar" and now "Spectrum," and she serves on the Avengers team led by Captain America/Sam Wilson.
Though it would obviously make the story too complex to include her as a Captain Marvel in the MCU, to have her as a character somewhere, perhaps in a law-enforcement officer role (she was introduced in the comics as a New Orleans harbor patrol officer) would be a nice tribute to the character and the heritage of the name.
What do you think needs to be in Captain Marvel's movie?