I wish to customize where packages and notebooks are saved by creating a custom directory tree which emulates Mathematica defaults. I wish to do this so that paths can be found in $ContextPath for loading packages. This will be done during development. Of course after packages (and other files) are proven to work they will be saved to Mathematica's default locations.
I recall finding a way to change in documentation for when Kernel is loading or when FrontEnd loads. But I can no longer find it.