I can tell that you're a big reader of fanfiction!
One thing I don't like about fanfiction is how things do not proceed linearly. Things branch off everytime a fanfic writer thinks up something different from the official story. Things get so difficult when you get so many tangents off from the official story. Also, if I find a fan scenario that I really like, it's likely to affect how I view the original story :/
Then again, my view of fanfiction is probably marred by what little fanfiction I've been exposed to. I've been directed to some by a friend, but they all had such bad grammar all I saw was an instruction to close the tab immediately.