The crux of netorare often lies in the theme of one character's emotional or relational defeat, so the main character occasionally acting as a loser fits that narrative. It's optional and you can take control of these affairs. Regarding the cock sizes, I'd declare the main character's is a regular size, occasionally he'll undergo temporary augmentation for specific scenes facilitated by the box.
Similarly, Melvin, the antagonist in the netorare storyline, typically possesses a comparable size but may undergo temporary enhancements in particular cases.
Are you proposing to add more netorare scenes?
It's currently a smaller part of the project compared to the rest, equalizing this would entail having a balanced fifty-fifty division between netorare and vanilla.