They need to create a Satanist character, to be more inclusive. And it has to be a hero, not a villain [\sarc].
Damian Hellstrom, The Son of Satan. Marvel character who first showed up in the mid-1970s.
Marvel went there in the 70s.
https://en.wikipedia.org/wiki/Daimon_Hellstrom
Encouraged by the success of the titles Ghost Rider and The Tomb of Dracula, both of which starred occult characters, Stan Lee proposed a series starring Satan, to be titled The Mark of Satan. Editor Roy Thomas had reservations about this idea and suggested a series focusing on the son of Satan instead.[1] (Due to an oversight, "The Mark of Satan" is mentioned in a blurb in Ghost Rider #1.[1][2])
...The character Daimon Hellstrom first appeared in Ghost Rider #1 (Sept. 1973), then was spun off into a feature, "Son of Satan", in Marvel Spotlight #1224 (Oct. 1973 Oct. 1975).[4] During the "Son of Satan" run, Marvel Spotlight was a controversial series, with numerous readers writing to object to the depictions of Satanism and Wiccanism as being either inaccurate or furthering the cause of evil. Nonetheless, sales were strong, prompting Marvel to launch the character into his own series, Son of Satan, written by John Warner.[1] The character's success faded soon after the series launch, and Son of Satan was cancelled with issue #7, though an unused fill-in was published as Son of Satan #8 (Feb. 1977).[1][5]
Hellstrom became a recurring character in The Defenders, Steve Gerber having added the character to the team during the time he was writing the "Son of Satan" feature in Marvel Spotlight, and Hellstrom continued to appear in Defenders following the cancellation of Marvel Spotlight. One of the later writers on Defenders, J. M. DeMatteis, featured a number of subplots focused on Daimon Hellstrom, commenting that he "was absolutely my favorite character. Characters like Son of Satan are a wonderful metaphor for what we all contain, good and evil, high and low aspirations. He's literally the son of the Devil, trying not to be what his father is. For a writer like me, how can you not feast on that?"[1] Hellstrom's story reaches a resolution of sorts in The Defenders #120-121 (JuneJuly 1983), as Hellstrom is freed from his satanic heritage and marries teammate Hellcat.[6]