Glad that you've found useful sections. I've always found reddit to be this generation's ExpertsExchange, based on quality of content. Perhaps I'm looking in the wrong places.
That would be Quora! But I agree, Reddit has pretty poor quality discussions, sometimes with as little depth as most Facebook comments.
This might just be my experience, but I've found Quora to be of extremely poor quality questions/answers with a few outliers. Reddit on the other hand seems to have both good answers and people just horsing around, but not as much astro-turfing as I find on Quora answers.
StackExchange consistently has the most technically informed content of any site I know. And the most focused / on-topic comments, which limits its social appeal of course.