I never got such a vibe from her or a sense that she finds her powers overly impressive. Agree to disagree there.
I'm not trying to justify it exactly, but do you really think the poor fair any better in Rautai or the Republics? You're going to find an impoverished underclasss in any sufficiently large society. The Huana trade social mobility, which is likely going to be pretty limited anywhere, in exchange for the underclass being cared for. Which seems to work pretty well outside of Neketaka. It's by no means a great system, but I can't say I find it worse than what the other factions offer.
Again a solution will be necessary in any society, and the prince actually is willing to try to find one. If the Watcher doesn't find a source of food, either the Dawnstars or smugglers, he doesn't have much to draw on to solve the problem, just swearing that he'll find a solution if it kills him. And take note that if you work with the prince the Roparu's conditions actually do improve. In contrast Rautai just evacuates the Gullett and burns it down, and Vailia doesn't do anything.
Enslaving dragons is bad, no argument here. But again, with the possible exception of Aeldys, all of the faction leaders would be up for exploiting the situation. Castol might wring his hands with guilt, but he'd still go along with it. The others wouldn't even hesitate.
The Huana are far from perfect, but their problems aren't unique to them, and they show more concern for their people than the alternatives do.