i can definitely say that i never saw the sequels going the way they did (time travel?? now the world is ending???)
while i do enjoy the game, there were a lot of moments when i was like 'i've been helping this guy with his restaurant and looking for items for this person for a long time now and not so much any main story'. you have 4 story-related main quests, and sazh's which is kind of not the same as the other main quests, and if you finish those then you're waiting until the last day before you can get any more any of the main story. the playtime for my first playthrough was 60-odd hours, but that wasn't made up of a large main story. lots of games have extra stuff (my god eater save is double that and sure as hell isn't main story stuff), but it seems like there's potentially a long time between main story segments if you finish things too soon. i think i had a few days where i was basically waiting for the 13th day (and then i ended up unlocking the 'lost time' 14th day so i had an extra day to wait).
if there was a way to try in the side quests to the main story, or have them add something like unlocking more back story or something, that would have been something. i suppose getting the 14th day and the dungeon with the last ones kind of gets you some extra story. but still, something like unlocking extra cutscenes or things like the fragments from ffxiii-2 would have been nice.
i will still play it more when my time frees up at bit, though