My summary of potential problems identified with Nadia:
1. The MC's reaction to her seems to make him too weak of a person.
2. Leah's reaction to her seems to make her too weak of a person, to the extent that her character may have changed. This may make Leah fans sad. They want dependable, no-nonsense Leah back.
3. Some players think Nadia has so overstepped the line that to enter into a relationship with her in the future is a no. She's just not worth the effort to reform. And even if she were to reform, it probably wouldn't be a believable reform. Also, a burned bridge remains a burned bridge. (This I think is the most difficult problem, if the story will lead to Nadia being in our harem. How to unburn a burned bridge?)
4. There could be some plot holes about Dik and how Nadia obtained her position. Background information could explain those.
5. Fear that Nadia will become the focus of the game, when we'd rather see more Scarlet, etc. . .
6. Not wanting to have to listen to Nadia's verbal denigrations and have the MC just listen and accept those. Nadia has unfortunately been put in a position where the MC can't shut her out. This is maybe too much reality for men who have to listen to women like this in their real lives. Women denigrate men all the time, and we don't enter into relationships with those women; and if by some unfortunate event we marry a woman who denigrates us, then we live a life of misery. We play a game to escape that repulsive behavior. But Nadia can't be shut out.
My summary of potential benefits of having Nadia.
1. Adversary who could add to the story and make the punishments more harsh. An island under Nadia's power is a terrible place to live. That could lead to good lewd content and motivation to get rid of Nadia for good.
And one obvious success:
1. If hachi wanted to create an adversary that the players hate: he did. Success. We dislike her intensely. That's good.
But . . . it's not the same dislike as we had with Sarah. Sarah was a horrible person, but her elitism was so extreme that it was also comical. You could laugh at Sarah while disliking her. I'll say that again: from first meeting her, you could always laugh at Sarah while disliking her. This is why the players have accepted her into the harem. Because you could laugh at Sarah's ridiculous elitism, the bridge to a relationship with her wasn't completely burned. So, is there a hidden unburned bridge that can reconcile us with Nadia?
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Edit: This game is a comedy, and it has a lighthearted feel that Nadia seems to change.
But . . . if there's a way we could laugh at Nadia while still disliking her . . . and there is . . .
Let's say Nadia ALWAYS talks to EVERYONE with this same denigrating language.
Let's say we even see her denigrating HERSELF while looking at herself in a mirror.
Then . . . the player thinks: Aha! I still dislike her, but she's a comical person now. That could be the beginning of a softening toward her.
But I'd still rather have her banished or killed ! ! !