Question to the ether, is there a meta walkthrough/write-up of the different paths/options?
No. I think someone (ffive maybe?) was really up on what the code said and pathing, but there is no official or unofficial walkthrough.
Why?
There's a LOT going on. For example, you might want to have a dropout Claire, but that requires certain stats being in a state at the end of HS. How do you get there? Well, there would be a bunch of things that you would need to avoid or target, but not necessarily all of them. It would be more of like 'do 3 of these 6 things'.
And that's for one result. What about pregnancy? what about becoming valedictorian? what about different results after Prom?
Each of those very, very few examples would need a similar list. It's a lot to work through for a singular result. Maybe it'll be something someone wants to do eventually, or maybe something we might spend dev time on when the game is further along and things are more set, but definitely will not be something we focus on in the short-term.
Play, experiment. There's variations aplenty.