It's been done plenty of times but you could go with the personality quiz trick. Steal the big 5 personality traits and score the player according to that, and give them speech options accordingly. Predetermine NPC disposition.
Using random numbers and clever game design, there's an infinite number of ways you can procedurally generate a story. The best way to do it heavily depends on what you're trying to do, skill and experience, time, and the point of your game.
Sometimes in all the jumbled numbers, the point of why people play the game gets lost and it gets tedious to play.
