I like a notebook feature! ...but then people may start asking for more features on top, like export the text, copy and paste, attach photos....?
Yeah it's probably out of the game's scope but a calendar that you could put like different coloured stars on certain days and input like a 15 character word next to the star so you could make up your own key for the colours and have simple text reminders would be so useful.
I would immediately put on turn 9 at the start of each playthrough Interview!!! since I always forget to plan in time.