Ooh, thanks for the rec. I think Critters might be one I haven't tried.

Interesting about plot/character. My plotting generally sucks, because everything I ever do is dictated by the fully three-dimensional, utterly real people who live in my brain and yell at me (and this is the part where you all back away slowly, not making eye contact...), meaning I write in a totally character-driven way that I then hack up and shovel around until I'm happy with it. I'm finding that's as true for fanfic as original, but with the added bonus of generally having someone else's plot framework to lean (lazily) on. It's a lovely rest.