You don't think giving Renee a "good ending" might take away from her status as an immediately recognizable threat, or even a villain? Presenting her in a vulnerable light from time to time is valid, because I don't think she's inhuman, but having her even have a small chance at a heel-face turn or redemption seems like it erodes the point of her character too much to justify that. Mallory, at least, grants the MC a real role in her overarching story as a sort of partner in crime, even if not as a real equal. I don't know if Renee would do that - she does not need one. She, unlike Mallory, is already wielding immense power and has the means to get whatever she wants, in a material/authoritative sense.
Your comments on Renee aside, I actually do really like NTR and such, but I admit something about the Valentine's day special made me more ambivalent than turned on. Maybe it's because I didn't feel any real connection to Priya and she just sort of came out with obvious emotional abuse from the get-go. She had no redeeming traits that I could see, so when the MC kept professing how much he loved her and how he knew she would do the same for him, it just came across as kind of shallow.