The credits for Hero for Hire #1 (June 1972) indicate that although Archie Goodwin wrote the comic and George Tuska drew it, they had some help from the "considerable creative contributions of: Roy Thomas and John Romita." A bit of the old internet research reveals that Thomas came up with the Luke Cage name (explained in the issue as his "new identity," because he's only known as "Lucas" in prison), which is a pretty badass name, of course, but is that enough to receive credit as a "considerable creative contribution"? And Romita apparently designed the costume, which obviously captures the rage and dignity of a righteous black man trying to make his way in a hostile world. Now, in Bendis's comics, he dresses like a longshoreman. So, yeah, I think the yellow shirt, chain-link belt, and tiara are enough to qualify as "considerable creative contributions."
The best thing about the early Hero for Hire comics is the dialogue, though, and since Bendis is known as, or thinks of himself as, a dialogue guy, it's easy to see why Luke Cage would be important to him.
Here's just a sample of the flavor of Luke Cage comics, circa 1972:
"...I'll be waitin', wise-apple...to break ya!"
"Those love taps may muss me, but they can't break me."
"What right you jokers got to sit behind those starched shirts, passin' judgement on me?"
"If the guard don't mind waitin'...I don't mind rappin'."
"You freakin' mealymouth!"
and, of course...
"Yeah! Outfit's kind hokey...But so what? All part of the Super-Hero scene."
That kind of dialogue, and the entire tone of Hero for Hire #1 invalidates the Ryan-Callahan-theory-of-comic-books-and-cinema, which postulates that American Superhero Comic Books are seven years behind the movie trends. Sweet Sweetback's Baadasssss Song and Shaft both came out only a year before the first Luke Cage issue. Marvel was on top of this trends! On top!
Of course, Black Lightning didn't premiere until five years later, so maybe the theory should be revised to say "DC Comics are seven years behind the movie trends."
Which fits quite well with the first issue of the Marv Wolfman's new Raven comic, billed as an "Emo Series." Donnie Darko came out in 2001. You do the math.