1. After Miss Emily's death, the decayed body of Homer Barron is found lying in her bed. Next to his pillow is another one, with an indentation as though someone has lain their head on it, and containing strands of Miss Emily's very identifiable hair.
2. The reordering of events prevents us from immediately connecting the dots, from understanding—definitively—that Emily was afraid of being abandoned (again), especially after Homer Barron loudly proclaimed that he wasn't the marrying type, that Emily purchased the rat poison to kill him and keep him with her, that the smell coming from her home was actually his actively decaying body. This reordering, then, allows us to develop some sympathy for Miss Emily as well as heightening our tension and the intrigue created by the story. If we can jump to the conclusion that she killed him right away, there is little mystery. We are kept in the dark as much as the people in the town were, and this is, frankly, much more interesting for the reader.
3. Faulkner's use of the first-person plural underscores the entire town's relationship with Miss Emily. She is symbolic of so much—the etiquette and social mores and traditions of the post-Civil War South—and the town thinks of her in this way. She is less like a person to them, and more like a symbol, and because they uniformly conceive of her in this way, it makes sense that they would be referred to in the plural.