Hmm... So either expand on the Journal or the Collection menu? o:
I'm asking bc your wording, "a simple encyclopedic catalogue on [what] quests or quest chains" (ignoring the 'what') already exists, technically. So those can be expanded further to allow people to know what they're missing and where they can start.
Kind of like how Mentor Roulette looks like when you haven't done the stuff that unlocks the content, except a bit more accessible. Such as...
"????" -> (player clicks on the missing questline and a prompt says) "Unlock Requirements: XYZ. Unlocked by speaking to the NPC at Place."
