Although including unlockables in stories is something I'm fond of, why would the author exclude choices from readers that are playing for the first time? Does certain items the protagonist gets by completing the game enter into the whole thing? (like, you get a jetpack if you get a certain ending, and so, if you play again, you can fly with the jetpack, and then other endings have other items like...I dunno, a lightsaber or something). Does information gained from the ending factor into this (like in a murder mystery story, if you've already solved the murder, you can just play the story and point at the murderer at the very beginning). How were you thinking of having these unlockables? Because I don't think having certain options that should be available to the protagonist at anytime (maybe you see a vent, but can only crawl through it if you've gone through the story before. Why wouldn't he be able to crawl through it in the first place?).
