The prophecy isn't about Furina at all, it's about the Fontainian people. Oo
Furina is very much a means to an end employed by Focalors, to give her time to charge up the Oratrice mecanique d'analyse cardinale™ in order to nuke the hydro throne and give Neuvilette back his power, because that is the only way to save the Oceanoid mimic population of Fontaine from dissolution in the Primordial sea when the bloody whale breaks out. (which is punishment from Celestia for the unauthorized creation of the mimic population by Focalors predecessor)
I get it, you are Furina fans (I like my lil' Gremlin too, enough to C2 her) but this whole quest is not just about Furina. Yeah Furina gets freed of her burden at the end but so does basically the entirety of the Fontaine when Neuvi forgives their original sin and turns them human.
If anything, this arc is about Neuvilettes development as much as it is about Furinas, because had it happened 450 years ago, Neuvi would just have said "f** the people, they deserve this!".
There is a reason why Focalors left him in charge of the state.
Bakool Ja Ja. Hated at first, then became best man. :'D
I think the main problem for a story like this is the darn MMO format. In Mass Effect you can really dive into the moral dilemma of "Do you consider the Geth alive" and give the player A CHOICE with consequences. That makes the story awesome. You can even design multiple alternative outcomes.
In an MMO, the path is fixed (else people couldn't play together). It doesn't matter what I think of the endless because the whole shabang is decided for me by the DEVs anyway. That's why the whole moral dilemma just falls flat on it's face and lacks impact.
Plus, the pacing was just forkin' horrible:
Me: Ooh big baddie charges up doomsday device! gotta do something!
Cahciua: Yeeah about that... it'll run y-cruncher for quite a while ... have some tasteless icecream instead and go do some utter trivialities.
I got legit ARR "cheese wars" flashbacks there and there is nothing I hate more than the story communicating URGENCY and the Writers throwing meaningless padding at me to delay the resolution. UGH.