Some of the basic quality parameters associated with a litmusbook (common to any form of code) & their meaning (in litmus context) are listed below:
Reliability: The experiment gives the same result under unchanged conditions (which includes test environment and versions of the components under test). In other words, the test does not provide random false positives/negatives.
Maintainability: The test playbook can be decomposed into well defined task files and utils that can be maintained & updated individually
Extensibility: An experiment with platform dependent tasks can be easily extended to run on other platforms with minimal implementation effort.
Usability: Often, the increasing test complexity can be gauged by a proliferation of user inputs (ENVs) in the litmus book. This is a judgement the user will have to make - to keep the test simple/focused, yet effective.