Would you give up fancy flashy FMV sequences in favour of things such as things such as unlockable/optional characters and user action based plots (eg. differing dates in FFVII)?

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I would, for what it's worth. I wouldn't mind a "trade-off" either - less fancy sequences, but differing depending on which characters you have unlocked. So the same total FMV (in minutes) on the disc but each play-through will only allow you to see something like 25-50% of them depending on how you play the game. Basically repeating FMV sequences with and without the various characters etc.

EDIT: Assume the story is awesome regardless of what happens, this is more about gameplay vs. realistic graphics.