I don't remember who said this, but he was some sort of composer, I'm certain. Probably from the 20th Century. Anyways, he said he never had problems composing within the boundaries of set rules (I think this might have been when we were talking about twelve-tone scales, which have REALLY strict compositional rules) but when someone said to him "just compose something" without giving him any sort of restrictions, it became so much more difficult. And I think that applies to fannish writing vs. original fic as well: once the set boundaries of the fandom and its characters, history, and mythology are taken away it adds a huge level of complexity that must be overcome to successfully write something (anything). I know I always have about a zillion (actually, more like five, but it feels like a zillion) ideas racing around my head for original stories and it's so hard for me to just develop one.

In short, it's hard. But you already knew that. And I would not be bored by any work you do, I'm certain.