Some time ago, I asked the authors on the board at the time if their Myriad Universe stories had grown in the telling, and initially had exceeded the 50,000-word level to one more befitting a stand-alone novel. I seem to recall Christopher saying back then that his contribution was written strictly at the 50k level, but don't remember if the other authors had mentioned if their entries ended up at the 80-100k level before editing for length.
As published,
The Tears of Eridanus runs about 55,000 words. I don't have the files on this computer, but I know that at some point there was an overrun of at least 10,000 words, maybe 15,000. But the book is better off with them lost. If it was to be expanded, it would be in following up or prequelizing, not putting new material within the story itself.