Hey Zeshio,
I think you have everything covered here. Some small suggestions that I would like to add to this discussion are:
- Try nail down the emotions or the message you want to convey to your audiences or anything that you wish to explore in the game. It should give you an insight on how to approach the story and narrative strategies to adopt.
- Work narrative based on that message.
- Let the player get feed back from their actions. This does not has to be all the time but just some unique place where you think it might pull off.
I know this might be things you already know, am just a beginner. But i hope it helps :)