The theology of comic books

(I considered titling this God and Comics at Yale to parody a once-famous book by William F. Buckley, but I didn’t. So if you run into my wife TYG, tell her that I do actually pass up the opportunity for a bad joke. Occasionally).
Comic-book geek that I am, I’ve been fascinated by the cosmology of comics for a while. What fascinates me is that while the Marvel and DC appear to resemble a monotheistic, more-or-less Christian universe, they’re actually not.
Both comic book universes have a single supreme deity. They have both a Heaven and a Hell. Characters who aren’t specifically devoted to some non-Christian deity usually wind up in infernal torment or going through Pearly Gates (DC also has purgatory—we’ll get back to that). We know a fair number of Biblical events happened, even if not in literal Biblical style (a lot of Genesis was explained in Dr. Strange as a battle between the demon-god Shuma-Gorath and the sorcerer Sise-Neg). Beyond that, however, they’re quite heretical.
For one, every pantheon of Gods exists: Greek, Babylonian, Hindu, Japanese, Asgardian. Buddha exists (as a deity) in Marvel; Islam works in DC (the Justice League battled Islam’s Satan-counterpart, Iblis, in one story). There are also fictional deities, such as those of the Hyborian Age (at Marvel, at least while they had the rights to Conan), and deities of alien races (though some of them, such as Krypton’s Rao or the Source of the New Gods, could pass as God under another name [though as Slacktivist notes, the implications of aliens in a Christian universe gets complicated]).
When the subject comes up, gods such as Thor will usually make it clear they’re only gods with a small “g” and that there’s a big creator-deity who outranks them. But given that the other pantheons can collect the souls of their worshippers (followers of Odin wind up in Valhalla or Hela’s domain, not Heaven or Hell), the comic-book worlds aren’t really monotheistic.
Even within the Heaven/Hell structure DC and Marvel don’t really conform. Damnation or salvation have nothing to do with what you believe in: If you’re really, really bad, you go to Hell; if you’re really, really good, you go to Heaven. In DC, at least, if you’re a good person who’s done a bad thing—even a monstrous thing—you may wind up in Purgatory instead (Hal Jordan, after butchering vast numbers of his fellow Green Lanterns in the godawful Emerald Dawn arc, winds in Purgatory; super-villains who’ve done much less have turned up in Hell). You can come back from both (I used to say that “going into the light” was the one proof of permanent death but both Green Arrow and the Thing have made it back from Heaven). Satan in Marvel, doesn’t exist (various underworld figures such as Mephisto simply take the name for their own purposes).
Within both universes, I think the explanation is simple. Several stories have suggested that you see the afterlife based on your own preconceptions (you don’t get Purgatory unless you have enough Catholic background to believe in it); as American culture is fairly saturated with Christian imagery, it’s not surprising if people of no fixed belief see a Christian afterlife.
Writing-wise, what we’ve got is people trying to tell entertaining stories in a world where anything can exist: Gods, demons, ETs, magic, superscience. More kinds of God or gods just means more stuff to employ: Christian faith in John Ostrander’s Spectre, Olympian deities in Wonder Woman. Creating a consistent cosmology isn’t a priority.
As a comics geek, I’m okay with that.