So there's a couple of threads now of people posting their beginning-of-game writeups, and it highlighted something about them that I like/dislike.
There seems to be some variations of how these are written, and I've come to think that the best have one thing in common: They are more about advancing fiction than mechanical bonuses
In my mind, the letters to the characters are about reintroducing them to the fiction at a run, rather than from a standstill. It's a way for them to feel like they are drawn in to what is going on, have some stake in the action, have ropes pulling them to and fro.
So the best are things like: "on a hit, choose 1, 7-9 choose two on a miss all 4 are true" like you see in Hatchet City. You list things about the narrative: now the player has to decide which of those things (in this case complicating for the character) are true, and it gives them something to deal/react to. Even the opposite, positive, if you give them fictional ties you give them something to act upon, and the rewards they get are the actions they take rather than just a numerical "gain +1 forward."
In many ways, it's also to help explain what's happened in the interim. sometimes people miss sessions, and when they do their characters tend to get sidelined. But they are still fictionally involved in the game, they still have a stake. In this way, you can make those intervening moments they weren't there for seem real and persuasive.
Sorry, I'm a little unfocused right now so I'm not sure how much sense that makes. What are peoples thoughts/questions?