Originally posted by Blanco Meow
None of the other games, so far as i know anyway, seem to have that. Their stories run their course, find their endings and close things up. Even if someone could find a decent springboard for a tangential sequel, it probably wouldn't find success because it wouldn't "fit" correctly; folks would feel the story was already far too "done."
*ahem* FFX-2? Although, I can't really see how the ending of FFX was open-ended. At all.