Perhaps it's a way for the author to explore different themes and challenge conventional character archetypes. The decision for her to be a villainess might be to create tension and drama in the manga's narrative.
One of the main themes is redemption. The villainess gets a second chance and tries to right her past wrongs. Another theme could be love, as she might develop new relationships different from her first life. And there's also the theme of power struggle within the story's setting.
In my opinion, the villainess is the most interesting character. She has so much depth, with her complex past and her attempts to rewrite her story. Then there are the antagonists from her first life who still pose threats in her second life. Their motives and actions add a lot of intrigue to the story. And don't forget any side characters who might help or hinder the villainess on her new path.
Maybe villager a sees the good in the villainess that others don't. There could be a hidden kindness or a tragic backstory that villager a has discovered.
One of the virtues could be her intelligence. In many villainess novels, the so - called villainess is often very smart. She is able to outwit those around her, even if her actions are sometimes misinterpreted as villainous. Another virtue might be her determination. Despite facing various difficulties and the negative perception of others, she continues to strive for her goals.
They are also presented in contrast to other characters. While the other characters may be weak - willed or overly dependent, the villainess with her virtues stands out. Her independence, for instance, becomes more obvious when compared to those who constantly seek help. Her loyalty, even if misplaced at first, makes her character more complex and interesting as it evolves throughout the story.
There could be her family members like her parents. They might play important roles in the story, either supporting or opposing her at different times.