@DLArmantrout Really interesting! I am always amazed by how specialized each industry can be. Not that I should be surprised -- illustration is full of all kinds of niches.
My knowledge on copyrights is due to a personal/professional interest in it. No formal training, just a lot of late night reading of IP law blogs. With that in mind I always want to be careful to note that mine are only opinions.
As for the Boldly Go case -- from what I gathered CBS/Star Trek have deemed this a tolerated infringement. They haven't issued a takedown notice for the book.
I do wonder about defending mash-ups under the Fair Use Defense though. The judge felt in this case that it was "sufficiently" creative. But that is arguably a personal judgment call. Would that same judge always think mashups of two IP's are creative enough to warrant protection under the Fair Use Defense?