You know, I am a very hard sell for crossovers because what I enjoy most about fanfiction is extrapolating from the onscreen chemistry we see.

I can certainly imagine how different characters from different shows might interact if they were thrown together, but for me that is a very very different thing that exploring or expanding upon the onscreen chemistry. And I enjoy it much less.

Another reason that crossovers are hard for me is that compared to most fans, I know very few canons. So most crossovers go right past me.