Ragara Adisa plans to invest heavily in An-Teng's agricultural products - peppers, tea, saffron, indigo: these are all valuable goods that require much more effort to grow in the Blessed Isle than in An-Teng. The looming civil war has already caused their prices to spike; they'll do so much more rapidly once she's in a position to control their export!
To do so, she needs to hold much more power in An-Teng than she currently does as a civilian and House representative, and so she has quietly put her vast wealth and myriad connections behind the Lilac Society, plotting to rise with their success. She does not disapprove of Shuri's actions morally; rather, she feels a sort of aesthetic displeasure at how wastefully
he exploits An-Teng - he could be making so much more money if he did things right! This, at least, is the explanation she gives when pressed as to why she's put her tremendous wealth and connections behind the Lilac Society.
Despite her cold exterior, Ragara Adisa has fallen deeply, irrevocably in love with one of her sworn brothers, a compassionate individual who does
care deeply about the suffering of the Tengese, but her marriage was arranged long before her birth, and she cannot escape it. If they triumph in An-Teng, she'll have the social and political capital to delay her marriage and pursue her love; if they fail and die, then she will die alongside the one she loves - better that, then to live another five hundred years in a stranger's bed!
She has held off on confessing her love because she sees no profit in it; even if it were reciprocated, it would only cause trouble.
(currently hunting for someone to play her crush, and/or a sworn brotherhood to join. Dun make me rewrite all this!