We don't have a unit testing framework in place, and we don't have a hardware setup for a system testing setup.
What we do currently is to let the buildserver attempt to build a number of sketches design to enable certain features in the library for all board types to validate that the features at least compile and don't produce warnings for the boards we support. Any sketch placed in the tests folder mentioned above will be automatically picked up and evaluated for all boards by the build server.
@oneyb thanks for your suggestion, and sorry for the late reply.
I worry that the install page is large enough as it is. People tend to be afraid of long texts, and just ignore stuff if there is too much text. Therefore, we try to keep the guides as minimal as possible, but still covering the most common cases. The full documentation is still available for those who want to dive deeper. If you have any idea on how to handle it differently, you're very welcome to speak up.