List three use cases in the project description

I am not sure use cases are needed. The module page extensibly describes what the module does. PWAs are still complex enough that if you do not understand concepts on the module page there is a good chance that installing this module won't do you much good.
I wish progressive web apps were as simple as flipping a switch, but we are not quite there in my opinion, and it is not this module's or Drupal's fault.