The character of Ms Marvel is heavily speculated to appear in the Marvel Cinematic Universe. She is touted to be their answer to Wonder Woman. Is it a question of "when" and not "if?"

Marvel does not have an iconic female character that would equal Wonder Woman in the comics. There were strong female characters in the X-men, but they were under-developed and they also belong to 20^th Century Fox.

From Marvel.Com's Countdown for the top female members of The Avengers, the strongest female character who became the leader of the team for an extended period is Janet Van Dyne aka The Wasp. However, that was partly due to her seniority (she was an original member) and affinity to Henry Pym (her husband, aka Ant-Man and co-founder of The Avengers).

The next two candidates are The Scarlet Witch (already in the film played by Elizabeth Olsen) and Ms. Marvel. Screenrant lists why Ms. Marvel should be the next badass babe for the onscreen version of Earth's Mightiest Heroes by sharing her origin story:

"If you're not all that familiar with the character, in the comics Ms. Marvel (a.k.a. Major Carol Danvers) started as an Air Force officer unknowingly working with alien superhero Captain Marvel. Later, as the result of an explosion involving alien technology, Danvers was gifted with powers including super strength, flight and enhanced agility and stamina. During the character's evolution through the '80s and '90s, she was also endowed with the cosmic powers of energy absorption and energy projection in the form of "photonic blasts." After fading into obscurity for a time, Ms. Marvel returned as a mainstream character in her own comic book series, and became a major character in the new incarnation of The Avengers in the 2000s."

Her powers are very cinematic, and they are also 'real powers' as opposed to Black Widow holding a gun.  She could actually fight in the frontlines, even against an alien invasion or wherever Marvel's Phase 3 leads us.

There were actually talks on who would play the character. From the Daily Mail:

"..British actresses Emily Blunt and Ruth Wilson are head-to-head in a race for the most sought-after new female role in Hollywood. 

Emily, 29, below, star of The  Young Victoria, and Ruth, 30, from TV's Luther, are both  hotly tipped to play superhero Ms Marvel in Avengers 2, the sequel to Avengers Assemble, one of the biggest box office hits of all time."