I pair with Philip Walton (who works for Google on Google Analytics) in this screencast. It complements the case-study we put together: Learning to Use Google Analytics More Effectively at CodePen.
I learned a ton about how Google Analytics works during all this. In a sense, it's dumber than you think. You can track whatever you want, you just need to send the right data. In another sense, it's super smart. By giving it just a smidge more information, you can extract a ton more out of it.
If you go in with specific questions, and take the time to implement the (pretty simple) bits necessary to track what you want, you can get the insight you need.
Plus it's free, for most of us, which is pretty huge.