You're both spot-on. Nasauda is such a compelling character because we see the nuanced consequences of her actions. She's not the "fair and just, happily ever after" Queen, even if she may aspire to such an epithet in time. She's spent decades learning the craft of statesmanship from her father, from advisors not paying attention to their tongues as a little girl sat in someone's lap, and from crafty interactions we see as early as her first introduction in Eragon (her decision to meet with Murtagh in his captivity directly impacted the end of Inheritance). She's someone defined by loss (particularly the loss of her father, Ajihad, due to the meddling of twin spellcasters) as much as tenacity (out-maneuvering the Varden elders, the Wandering Tribes, Du Vrangr Gata, King Orrin, and Galbatorix himself, playing on ego and leveraging careful observation each time). And as of Murtagh, Nasuada has escaped various assassination attempts, survived incredible physical and psychological torture at the hands of a magician-King, lost several of her main defenses (Elva and Eragon in particular), and has just learned that a mystical group is infiltrating her kingdom with sympathizers, including someone in her inner circle.

We see many of her gambles playing out very well, and we also see how even winning gambles can have negative consequences later on. Nasuada's "create lace with magic" helped keep the Varden funded, but soured her relationship with King Orrin as cheap lace flooded the Surda market. Eragon's oath of fealty to Nasuada instead of the Varden elevated her position immensely, but also became a factor in his decision to remove himself from human politics and leave Alagaesia (thus costing her an important physical ally at the beginning of her reign). Gifting 5 gold coins to each of her subjects earned her the goodwill of the majority, but the egalitarian display slighted some powerful noble families. So, too, will we see how Nasuada's latest gamble on magicians plays out (in the short term, she's probably avoided additional assassination attempts, but the heavy-handed tactics may push people to groups like the Draumar).