I’m not sure why you are so positive on twitch reporting. It’s far from the land of perfection you describe. They don’t act on lots of reports I make that are clearly against ToS, and actionable.
As for UserVoice, I refuse to signup for yet another website, where I don’t agree with their privacy policy. I don’t understand why an Amazon company can’t have their own forums for suggestions, like here for devs. I’ve suggested things to @twitchsupport on twitter, but they choose to ignore my suggestions. So, I’ve stopped posting any more suggestions.