I am feeling your confusion with the documentation and debugging. However, I don’t think the situation on either is any better in virtually any general-purpose language. Speaking from personal experience, the processes you’ve described are way more terrible in Python, C, C++ and JavaScript, all considered first-class programming languages. Since the other languages have been floating around longer, they usually have the IDEs and other tools that remedy such terribility.
Here are simple possible workarounds for your points:
2. reading the standard library’s source definitions yourself (e.g. in GitHub - JuliaLang/julia: The Julia Programming Language), as they are (mostly) written in Julia and not C/C++
3. extensively using @which and other interactive utilities
That may or may not help you, but then again, I don’t think what you’re asking for is easy to give.
Edit: this thread is also worth checking: What Juno features do you use most?