We've done a lot of work the past few years on making the system more flexible and are constantly working on improving the documentation, especially the installation instructions - and the more people that are able to get the system going, the more contributions we've seen.
Still, the docs have been mostly focused on getting a developer install for hacking on the system, and less so on installing and upgrading the software without having to configure and understand every component.
In response to some specific questions on the mailing list about how to install and then upgrade Socorro, we've released the deploy script that Mozilla uses internally (with some modifications to work in a more vanilla environment).
We also run a Jenkins bot to ensure that the Vagrant and deploy script don't regress.
This is easy enough that it's making our "Installing from source" instructions look quite baroque, so expect those to see some improvements soon too!