Concerning interpretations of Faulkner's "A Rose for Emily," I haven't read Faulkner's own interpretation of his story. In fact, it would be unusual for a writer to give a detailed interpretation of his own story. Thus, I can't give an alternative interpretation to Faulkner's, since I don't know what his is.
I can give a legitimate, relevant, and appropriate alternative interpretation or way to analyze the story, however. Alternative, that is, to the traditional interpretations of the story. I don't know if the traditional is consistent with Faulkner's or not.
One could study the character of Emily in terms of modern psychology. Psychology was in its early stages when Faulkner wrote the story, and brain science did not exist then--at least not on any level equal to what's going on today.
Thus, one could investigate Emily's refusal to let go; her sheltered childhood; her reaction to her economic and social fall from grace; her refusal to change; her refusal to give up her father's body; her murdering of Homer; and her necrophilia from a psychological perspective.
To use a cliche, the character of Emily should provide a field day for a psychological study, and provide you with an alternative interpretation.
Interesting question- I am sure you will get more perspective answers.
Faulkner presents us with a stamp of the Old South, and how hard it is for some to shift paradigms in times of change. Emily itself represents the inability to let go of the past to a morbid point in which her psyche and her mentality are affected. Because of this, one would conclude that Faulkner's interpretation of the Southern culture is one which could be categorized as dignified, stubborn, and hard to change for the sake of changing.
We could detour from his interpretation by actually attacking Emily rather than taking the time (which both the narrator and reader do) to understand her situation. We could interpret her stubborness as the doings of a mean old lady, her inability to change as a sign of defiance, and her posession of the body of Homer as a mere morbid and disgusting sudden action.
However, we tend to agree with Faulkner: We take pity in Emily, and even the Colonel himself sees that there is not an inch of malice in the woman: She is just lost in a new world.
Therefore, to be against Emily would be to completely deviate from the purpose of Faulkner's description of her.