A development editor would be fantastic as well, I honestly just didn't know where to find one!
Ie - did you wait for your first completed draft before showing them the whole thing, or did you show them chapter/scene works-in-progress as you wrote them?
The consistent feedback I received from those readers weighed heavily on the major edit which followed. I had made some mistakes, no doubt about it. The work is now better for it.
I then gave the "finished" book to a much smaller group of beta readers and repeated the process. Then I went through the book a few times myself to improve the flow. Finally, it went to the copyeditor.
What is Lean Media? It’s an approach to creating media content that emphasizes low-cost production, careful observation/measurement of audience feedback, and fast iteration. Properly incubated and carefully scaled, Lean Media projects can attract loyal audiences and grow into successful works and brands.
(more information via http://leanmedia.org)
Would you be interested in being profiled on the blog about your approach to using beta readers? If so please email me at ian -at- leanmedia.org ... I think what you are doing would provide a great example!