According to the cast page, Wanda is a member of the lost Croatan tribe. If "lost' means they are extinct, then the tragedy of her tribe's extinction would help explain why Wanda has lost her capacity for hope.
Losing her own tribe was painful enough, but since she's found a new home with the Plaid tribe, she been forced to watch the decline of the Plaid, to the status of a nearly lost tribe.

These factors may help explain why Wanda continues to serve Lord Stanley, even though she is clearly a more talented manager than he is. Not being a member of the Plaid tribe may be a political liability for her, but it's also possible that she feels the Plaid tribe's situation is so bad that she couldn't make it better, even if she did take over.

She seems to still be trying to find a way to prevent the final downfall of the Plaid, assuming her suggestion that they spend the funds needed to acquire the Perfect Warlord didn't conceal an ulterior motive. (It's possible she has some reason for making the suggestion to Lord Stanley beyond the hope that the summoned warlord might salvage a desperate situation.)
Patience is one of her strengths, so she probably hopes that even if the Plaid tribe follows the Croatan into extinction, she will still find a way to survive. Lord Stanley is also thinking about how he can survive the downfall of the Plaid, since he intends, if the capital city falls, to take the Arkenhammer and flee.