Story, is OK. It could have stood to be a little longer, but it was good enough to be put out the door with how long it took to make it. Whether it and the characters will stand up as well as the ones from 4 through 9 though, only time will tell, but I'm betting no.
(Sazh is the standout, decent personal story. And I've seen his VA in the Sci-Fi show The Chronicle, and considering the mans normal voice, he did one HELL of a performance for this game.)
The Fal'Cie are poorly represented, especially the Pulsian ones, and the cause for the War of Transgressions. (though I do not have all the analects datalogs yet) And no epic fight against the gigantic one you see while walking on the steppe? C'MAN. (Probably add it into the remix version -.-)
Why the first of the thirteen days happened, and happened then, could use a better explanation.
The PSICOM officers needed more screentime/chase to make them better antagonists, Rosch didn't appear nearly enough to make his last appearance really click right.
Also, the Eidolons need more story. Brynhildr/Hecatonchire/Alexander especially get shafted.
And yeah, the linearity blows. Not being able to revisit anything from before chapter eleven only makes it worse. And the beach bar + early Nautilus being the only non-combat locations in the game. Fail.
Lastly, the gil situation blows. Yes gil not dropping from random battles has more verisimilitude, but there is just not enough ways to get the stuff easily.