One of the issues with making a scene replay gallery is that a lot of scenes will play out differently depending on the game state from the choices you've made so far and the relationships you're in.Of all the games that could use a banger scene gallery mod, it amazes me the most that this one lacks it. I've replayed the main plot of this one to see two or three new scenes more than any other game.
So to setup a scene replay feature we'd need you to go through a survey of questions appropriate to each scene to set the variables where they need to be so things don't break and play out properly.