I remember working on a simple peer-peer chat using WebRTC [1] and it took me a long time to actually grok what the whole protocol was and how it worked, even with off-the-shelf libraries available. This would have saved me so much time!
It is really empowering to build stuff quickly. When you hit that wall of abstraction it is so frustrating (especially when debugging).
If there are any topics/ideas you have would love to hear! I want this to be a community owned resource.