I'm not sure if it can even be considered manipulative, since I'm about 100% certain she actually believes she'd go through with it. Besides, she isn't doing it to exert control over her father - she is doing it to assert her own control of her own life decisions. Give me freedom or give me death, that sort of thing.
It seems clear to me that her father has been led to believe (likely by the Temple, which has conspired to keep the Light bloodlines as isolated and diluted as possible, probably because the recessiveness of the Light element is just a myth that hides blah blah blah plot) that the rumours about the Louvremonts barely even scratch the surface. So for now I'm just fine with Aisha proving to be assertive and unflappable; let's hope her poor father doesn't suffer a heart attack.
Anyway, just take a step back and consider what you're advocating she do. She's been reborn into a patriarchal society in which the nobility treats their daughters as game pieces and financial assets. Why would she have to cater to that? She's literally paying her own dowry. Why shouldn't she expect the personal freedom that was promised to her?