Space Opera Q2: The "Plot" and structure
The book didn't have so much as a "plot" as an excuse for a sequence of bizarre situations. Even the "eliminate a competitor" conflicts near the end of the book were rather tacked-on. On the other hand, books like "Harry Potter and the Philosopher's Stone" and even "The Hitchhiker's Guide to the Galaxy" had about as much plot as "Space Opera", so is plot over-rated?
Related to this is the structure of the book, with alternate chapters of background exposition and the trials of the Decibels. Did that work for you? Did you like having exposition, or should it have been worked into the main sequence of events?