It depends on your preferences. Some people might find it amazing due to the rich story and immersive world-building, while others might have different opinions.
It's hard to determine a single best story quest. 'The Story of Klee' is popular among many players for its charming and light-hearted narrative. Different quests appeal to different people based on their interests in the game's world and characters.
Mystery is also a common theme. There are fanfictions where the origin or true nature of certain elemental reactions is a mystery. The characters then embark on a journey to uncover the secrets. Additionally, some fanfictions focus on the cultural aspects of Genshin Impact, and how different regions have different attitudes towards elemental reactions.
It varies. Some character story quests can be completed in a couple of hours, while others might take longer depending on your playstyle and exploration.
Sure. 'Amber's Elemental Reaction' is a great one. It focuses on Amber's different reactions during battles and how they affect the story's progression. Another good piece is 'Reactions in Liyue', which dives deep into how the characters in Liyue Harbor experience and utilize elemental reactions.