Vash is so idealistic in the anime that it takes attention away from those traits. He seems to enjoy his abilities when he's using them in a playful way (e.g. toying with the bounty hunters), but when it comes to the real ultra-violence, he gets preachy. It's not that I think that he's sadistic in the manga, but he seems to get that rush from fighting and being good at it. I think these traits are definitely in the anime, they are just expressed a bit differently. But Nightow and his Vash own my soul, so I'm probably biased.;)

The disempowerment/victimization thing seems to be more common in woman-centered fandoms, where sometimes I read a story and sense an almost pathological need to punish and disempower the character because she's too strong. And all too often there's rape involved. Detestable. But I haven't been in a lot of fandoms, so hopefully I'm wrong about how prevalent this is.