My absolutely favorite aspect of FFXIII was the astoundingly large menu and bestiary. I would love for a similar amount of information to be available for the player to read at will. I agree including some kind of scan would be a nice way to collect information on each mob type, even if only killing the mob type once is required (which I think is very reasonable). I could honestly see myself spending hours reading information regarding lore on the main storyline, races, nations, monsters, Notorious Monsters, etc.