Aside from the fact that not everything needs to be sequelised (in this case, sequelised again), I suppose there is potentially some very good stuff that can be touched on and explored, either for the first time or further, in an FFX-related expanded universe.
The issue with fiends still populating Spira, and presumably recent Unsent still wandering around the world have been passed over in FFX-2, and an expanded universe story can delve some focus into the people in Spira who lack the powers to summon Aeons, but will presumably still possess the ability to do their haunting exorcist dances. Kurugum appears to be one of the people filling in this "Sender" role, and I'm glad for that, because official material (as far as I know of if it hadn't already) clearly answers the question of what is to be done about the vengeful dead.
Chuami being this righteous atheist quick to denounce everything Yevon I think has been an overdue idea. I thought FFX-2 could have done with something more akin to this rather than focus on some vague conflict between two factions with equally vague ethos, but I suppose after only two years, it's too soon for new ideas and thoughts to be properly rationalised and settled on. Still, good to see potential road for a more sociological exploration of post-Yevon Spira. Can firm radical thinkers like Chuami accommodate with moderate conservatives who recognise the good social boons of Yevonite practices despite it being you know, a discredited farce?
Tidus's return and the metaphysics of Spira and the Farplane. Has his return at the end of FFX-2 caused some form of instability that otherwise would have been normal? Was Yuna risking in some form the very calm she firmly battled twice for by essentially requesting the Fayth in question to dream "back" Tidus? If so, perhaps Tidus's second resurrection has been the straw to break the camel's back, leading to a gradual amalgamation/leaking over of the Farplane with/over to Spira, with sentient Pyrefly shapes of the deceased, and someone allegedly "wishing" for Sin's return? Has Yuna theoretically doomed her own calm, and what psychological effect might this have on her?
But if what the novelette supposedly has is genuine as reported, what the heck, Nojima? Do you just really hate Tidus? I mean, it's almost like Spoony took control of the man's mind and hand, and forcibly wrote in a part to kill off Tidus in an outlandishly cartoony and gory way just to get the message across about how much he despises Tidus. It's kind of hard for me to accept this as something to take very seriously, you know, if I have to roll with the idea of a strangely mentally-regressed Tidus excitedly rushing up to a Blitzball and kicking it around culminating in Yuna passing out at the sight of a surprised-looking decapitated head rolling around next to her.
I still maintain that an edge of awkward tween drama isn't something I'm looking forward to. But I suppose at least we now may have context for the state of the relationship between Yuna and Tidus, even if the behaviour in the audio drama (which is surprisingly not as offensive as I first thought it would be) still irks me. AndI suppose I can at least rationalise a bit of it. Yuna declaring that she has another man may well be a lie. It's a ruse to get Tidus to stay away from her while she contemplates a new way of ridding Sin again, in the context of her fright at the thought of what Tidus currently is, and the fragility of his existence and their time together remaining.
tl;dr, the audio drama not as bad as I feared, but the novelette's bomb thing is still baffling and daft.
EDIT: Who wants to imagine a potential FFX-3 as a dark comedy with Tidus as the equivalent of South Park's Kenny?