Is Eurdora Welty a great American writer?

Eudora Welty's story Why I Live at the P.O., in her "Collected Stories," is justifiably one of her most famous, and if you didn't know is the source of the name "Eudora" for one of the earlier e-mail programs. More than any other, I think, this established her as one of the triumvirate of 20th-century Southern writers, each with many similarities (what makes them specific to their region and not just writers of the same place and era) and stark differences (what makes them great), I'm obviously thinking of Flannery O'Connor, whom I posted about yesterday, and Faulkner: yes, they all are comic, are you surprised? There are some truly risible passages of dialogue throughout Faulkner, especially in Sound and the Fury and As I Lay Dying - but he's a far more interior writer, and far more tendentious, at times pretentious, than EW or FO'C. Those two have many more similarities, as noted, but Welty it seems to me has a lighter touch, she's not as drawn to the gothic or the grotesque, but, like O'Connor (and Faulkner, too) has a great affection for the Southern working class and rednecks, a great ear for dialect, and an arch comic style, very evident in P.O. - you can see, in the characters talking past one another, the quips and cuts, the self-aggrandizement and self-importance, the style that evolved into the weird fiction of George Saunders or the zaniness of the short-lived JK Toole. The question for Welty always: Is there more than meets the eye? Is her comedy just a precursor to Steel Magnolias and a thousand sitcoms, or is she playing for greater stakes? I will keep reading the Collected Stories to get a sense of why, and whether, Welty is a great American writer.