Ciao! This is all gold thank for sharing! I agree that consistency is the key. But it is the key in many fields this is why well-designed abstractions or continuous integration exists. To enforce consistency.

Error handling as well can be very helpful to communicate what your system is doing, but errors are not the only state you want to look for.

In theory, but it is something that I didn't see used too much a logging library can be wrapped into an abstraction where useful to enforce consistency. For example if wrap your library in something that conventionally sounds like "ThisLoggerIsCriticalDontMoveItAsYouWillDoWithOtherLogs(logger)" you are communicating something more about how that.