(ShB Spoilers) Didn't Hydaelyn, uh...

[Absimiliard]

Stuff

A few observations here:
- Primals do typically have a will of their own. While yes, it is shaped largely by their summoners, Ramuh and Alexander are not the only ones to choose a different path. Odin was originally summoned to be a destroyer but chose the life of a simple warrior, wandering from place to place in search of a true challenge. It is his fondest wish that one of his deaths at last leave Zantetsuken depleted so that he can finally end.
- Barring a retcon, Hydaelyn does indeed possess a will of her own. Everything she's done, she's done so because she chose it. It's debatable whether defeating Zodiark also falls under this, however. We can't ascertain whether or not her will came after her summoners had been essentially unmade by the sundering.
- The vast majority of the Spoken races present in the world of Final Fantasy XIV are sundered Ascian souls. Only the lesser races would perish in resurrecting the Ascians within Zodiark.
- Near as anyone can tell (and as hinted by official sources) the Ascians still have their own free will. Whatever Zodiark tempering them did, robbing them of the ability to make their own decisions apparently was not part of it.
- It stands to reason that life as a whole would be better for everyone if the rejoining were allowed to proceed unimpeded. No one would ever be sick, hungry, homeless or impoverished again. There would be no wars, no pain, no conflict of any sort beyond harmless intellectual debate. Everyone would again live in a star-spanning utopian society, a shining future awaiting all those who dwell upon that world.
- Zodiark himself does not appear to have been even the least bit wicked. It sought - unsuccessfully at first - to revitalize the world at the request of his summoners. Finding his power wanting after having already saved the world, the Ascians made a willing sacrifice to give him the necessary strength to carry out their wishes a second time. The convocation wanting to sacrifice the plethora of life that sprang up on their world after Zodiark revitalized it was their decision alone, as was the decision to make another sacrifice. It does not appear that Zodiark ever asked for more souls. Provided this rings true, that would mean Hydaelyn effectively annihilated the only extant sapient species on that world - and the world itself, essentially - for no reason other than the fact that a minority of Ascian society strongly disagreed with using new, non-intelligent life to restore the lives of intelligent, sapient creatures that had made the ultimate sacrifice for their world and their people.