I have to agree with you there Iggy - it used to be that you could find really well written fan fiction just by logging on - and now you have junk that's got so many misspellings and hatefulness that it hurts the brain. I think that's why I started writing it to tell you the truth - so that I'd have something to read.
As far as bashing one character because you don't like them. I really hate one character in my chosen fandom of FF VIII - but I still use Rinoa. Granted most of the time she's just a plot piece and I have killed her once - but it's always to further the story - never because I can't stand her. If I could ignore her I would, but because she's Squall's cannon - I have to do something with her to get her out of the way. Unfortunately she usually turns out to be a bitch, but I thought she was in the game. Sometimes weak equals bitch to me I guess.
Lord knows I try to be good, and I try not to bash the characters I don't like, but it's hard sometimes. Especially when you can't seem to get away from them. I just don't go out and intentionally write a fic in the I hate so and so vein. Maybe I should write a Squall/Rinoa fic and just get it out of my system.