The merits of comic books

I just finished rereading the first volume of Neil Gaiman's "Sandman" series, and it got me to thinking about comic books. "Sandman" is an excellent comic book. "Archie", for the most part, is not. What, exactly is the difference? In a sense, the question is an easy one. The characters in "Sandman" are much more interesting and developed. (I've often wondered why, after 40 or so years of fighting over Arche, how Betty and Veronica have both remained friends and not killed him. There is nothing remotely realistic about that love triangle.) The illustrations in "Sandman" are beautiful. The stories are epic and interesting. This is not just a rehash of the old popular vs. high art question, because Gaiman straddles the line. I think the real answer to my question, though, lies in the fact that Neil Gaiman makes better use of the medium. The strength of the comic book, in my opinion, is it's ability to invent a world. Even the weaker ones do it, to an extent. In the "Archie" comics we have an entire little universe in the town (I forget the name) where Archie lives. The world of the "Sandman" comics is just much, much realer, despite it's fantastic nature. Why is this the strength of comic books? I can't say I'm 100% sure, but I have a theory. The comic book has an ability that no other literary form has. A comic book artist has the ability to take a completely irrelevant character and make him real. How? By drawing him. A novelist, a short story writer or a playwriter do not have the luxury. Irrelevancies really do detract from these forms. But, because the comic book is also a visual art, it gives the artist the ability to create detailed irrelevance. And that is what lets him build worlds.