OK, made it...
Eden
So Gaia's "faerie" was Mitron the whole time, and she was really a reincarnated Loghrif, and the latter was the first choice for Zodiark's heart, and the former had a sorceress knight relationship with the latter back in the day? Unexpected.
And so the whole truth of the Flood is revealed: Ardbert's Blade of Light only killed Loghrif and instead warped Mitron into Eden, who later kickstarted the Flood. Thus came the Sin Eaters and all that sprang from them.
The fact Emet-Selch did nothing about Mitron cuz "I can just get another" really does put a damper on my opinion of him. Kinda explains Fandaniel's disdain for the unsundered Ancients; while they may be more valuable for being Ascian incarnations, they were still redundant in the eyes of the Big Three.
None of the fights were particularly difficult; only got a full wipe on E10, and only cuz the healers were bein' dumb.
So, uhh... that's just where it ends? We don't get to see this festival? Or is it the all 4 Role Quest extension (I can't get cuz I'm too lazy to bother leveling ACN)?
And that was prolly Ryne's last big hurrah. Goodbye, precious cinnamon roll!
VIII References in Eden's Promise
There are a fair number, but only in the latter half (duh). Some people may have pointed at least some of these out, but -
Like GFs making people forget things as a cost for using them, Mitron forcefully makes Gaia forget her current incarnation's memories.
Loghrif and Mitron have a Sorceress / Knight relationship.
The Fatebreaker is similar in spirit to Griever, being based on people Ryne thinks of as the most powerful (Thancred, Ran'jit, and to a lesser extent Vauthry / Sin Eaters). Appropriately he uses a remix of "The Legendary Beast," Griever's theme from VIII.
Eden's Promise using Draw, Cast, Stock, and Junction are all references to VIII's para-magic system.
Gaia wandering through the dark void before collapsing, only to be saved by Ryne's voice and awaken in a verdant field is taken almost shot for shot from the ending of VIII, where Squall wanders through compressed time until Rinoa saves him much to the same effect.
Gaia's speech when entering Final Form in E12S echoes Ultimecia's, and the song that plays after is the awaited Soken remix of "The Extreme." (Will have to wait for a vid to listen.)
Mitron's true name, "Artemis," is likely a reference to Ultimecia's original JP name, "Artemisia," an ancient Persian queen. The name is also a common "witch name" in Italian. Odd they chose a female deity to be a male's true name, but w/e.
Side thoughts:
Werlyt is very obviously meant to be Gaius' "redemption" story, or at least show he is truly repentant for his actions. Still, it only really works because he's up against Valens, whose depravity rivals (if not exceeds) that of Zenos.
I'm fine with characters not dying all the time, and pretty much expected the fakeout with Merlwyb. "Obviously she's going to offer her life, and obviously the kobold isn't gonna take it; this isn't that kind of story."
I never considered IX all that "gritty;" on the contrary it's the most optimistic of the PSX titles, even if it does have a deep message (value the time life gives you). Never booted up Tactics on anything (and have no interest in doing so), and only got to the Sochen Cave Palace in XII before deciding it wasn't really a game for me. Various reasons. But I know plenty about the two cuz people won't shut up about them... and this game crams references to them down my throat...
Well, guess that's 'bout it. Back to the daily grind on the morrow.