I'm comparing her to a religious god because no other scale is particularly functional as a comparison. I actually went through some others; comparing her to the sun doesn't work because the sun doesn't have agency, and comparing her to a politician who shaped a nation doesn't work because people in-story definitely don't look at her the same way people look at, say, Lincoln. Technically speaking the closest example would've been to go for a Greek god like Zeus, because those myths were very formed by the notion of gods being temperamental and human, but we don't really have reliable and close-at-hand knowledge of how regular-ass ancient Greeks considered them. I finally landed on Judaism specifically because a level of adversity towards their god is actually a fairly commonplace part of their belief system; rather than how Christianity broadly does go 'god giveth and god taketh', Judaism actually does believe that their god is a complex figure that, while he may broadly be on their side, doesn't mean he's perfect or that they shouldn't take umbrage with him sometimes.
The thing about saying 'her methods resulted in a lower average quality of life' isn't broadly true, though, because the main people who were put out of place by it were the Ancients. You might go and say 'but those are people so all people were hurt', but we have a funny piece of evidence there: not every spoken person in the sundered world would have been an Ancient, because that's what the Echo is a mark of. Someone like the WoL might have very specifically lived better, but most people don't have that despite having the chance to awaken it; none of the 'A-tier Scions' would have been, Nidhana wouldn't have been, Raubahn wouldn't have been, Aymeric wouldn't have been... I don't know who your favorite characters are, but unless you very specifically only like Emet, Hyth, Ysayle, Krile and Arenvald, very few of your favorite characters would have actually had that guarantee that life would've been better without her. In fact, the argument is pretty clear that most of those lives wouldn't have existed at all without her, especially given the specter of Zodiark's sacrifices.