I think it'd be better if you were looking at this story not as one based 100% on realism, but rather as a mechanism with specifically chosen decisions made to create certain emotions in the reader, within the writer's own tolerances.
The main reason why love is what amplifies a dude's abilities is because the alternatives too dark. And the writers don't want to go there, for whatever reason. Maybe it wouldn't be fun or too depressing to write, or they think no one would enjoy reading it. It's clear they want to write darker LIs, but have a personal line drawn.
The other reason I can come up with, as to why they chose that route, is because it helps in creating personal drama. You can love someone and still hate them, after all. Be disgusted with yourself for loving someone you know is manipulating you. Have doubt they actually love you back (which is a fairly justified feeling in this particular story's case).
My impression of the plot is that it's going to be more of a psychological thriller, with the main conflict being of the MC dealing with her situation and the feelings from it. A concentration on the characters versing themselves and each other, rather than them versing an outside force like Atlids. Because of this, I don't think you gonna get what you're hoping for out of this story.
I agree with you that they should try and give the "must love a guy" point a bit stronger a leg to stand on. But I don't believe the writers are gonna remove that plot point, for the reasons above.