I believe that's part of the motivation behind bounties: if I've invested a lot of time and accumulated karma, I can spend that karma to improve the quality/speed of answering my question.

Re: TwoToReal. It's an interesting idea, although it seems like it adds burden to the answerer. One quality I like of SO is that it encourages people to ask better questions (keep concise, provide relevant details, etc), but in a system where I'd be getting real-time help I might become lazier about posting my question. "I have a problem with node.js" rather than "I'm getting this output when trying to use node in this way".