From her writing in To Kill a Mockingbird, I think Harper Lee believes there are practices in the South that must be stopped.
It is too simplistic to suggest that Harper Lee dislikes the South. She was born and raised in the South, and her life mirrors Scout's. It is clear that she sees the flaws in Southern life; she illuminates them in To Kill a Mockingbird. One such flaw was the racism that dominated the South. When Scout says, "There's only one kind of folks, folks," it is a statement about what is not practiced in the South. Lee thinks that Scout's words are a model of behavior to which people in the South must aspire. In other words, having Scout speak so profoundly, Harper Lee believes that people in the South do not demonstrate such acceptance and should change.
Another example of what Harper Lee thinks about the South can be seen in the title itself. Atticus tells Scout and Jem that they should not shoot at a mockingbird with their air rifles because they “don't do one thing but sing their hearts out for us." Atticus precedes this by telling them it is a "sin to kill a mockingbird." Harper Lee believes that there are victimized people in the South. She believes that they "sing their heart out" and still are targeted. Because she has Atticus speak powerfully about the dispossessed, it is clear that Lee believes that injustice exists and it must be addressed.
Harper Lee would not construct a novel with dominant themes of racism and injustice unless she saw those realities in the world around her. She recognized that what was happening in the Southern part of the United States was morally and legally wrong. She has Atticus and Scout address this injustice. Harper Lee has her characters articulate such ethical truths, highlighting the limitations of Southern society. At the same time, her novel provides a window to a better world. Just as Scout comes around about Boo Radley, Lee believes that the South is capable of change if it has the courage to accept the need to do so. While she sees the South as a "deeply flawed society," Harper Lee also believes that "folks" have the capacity to change the world and their place in it.