There are actually documents in the works right now that address all of the above issues that you mentioned. I am also glad to hear that the documents in their current state helped you approach the Gameplay Abilities as this leads me to believe we are on the right track. This is a really hard system to document in a meaningful way as it is really complex with lots of moving parts. Make sure to check back when this is released. We are planning to do a lot more with this sample project than we have done with past sample projects. In the meantime, if you have any other suggestions please let me know so I can make sure it gets noted.