I have this slide that just shows all the parts of the system we have dedicated whitepapers for and it is huge. Please keep in mind that this project tries to accomplish a big thing and that requires a lot of work on various parts.
As the system has many components, it is hard to say where to "get started". It really depends whether one is interested in building Apps with/on top of it (safe_app_nodejs probably) and do client side work (safe_client_libs) or is interested in the network layers (crust, routing) or the behaviour of full-nodes (valut).
I appreciate that code is split up into many separate repositories, as that also comes with the idea that these components can be used outside of this project - like self_encryption or system-uri, which even have little other maidsafe dependencies. And many of those aren't "active" because they are just "stable". Like self_encryption. It works. It is great. It can be used independently as a command line tool. No need to touch its code base on a weekly basis.
I agree however, that we probably need to provide a map and some guidance on how to understand all of these. There is a lot of space to cover.