For me it's a tie between Zoe and River.

Zoe is just not the type of woman or fictitious character that does anything for me, neither as far as looks nor personality go. "What this marriage needs is one less husband": You said it, Wash.

River would have turned into a problem for the show, had it run longer. Her walking around barefoot acting like a moping teenage Emo kid would have gotten old very soon, it already started to get on my nerves after a few episodes. At least she got better in the movie.

How about you? And don't say they are all great, in a way they are, but who did you find most negligible and why?