Actually I think similar projects worked for scientists doing lengthy computer simulations. As far as I remember they recruited the general public not their peers, because their 'peers'  also used their computers to full capacity. At the moment I am using my computer full time so I wont be able to contribute much. (I also dont have any renders that take less than a couple of hours).
I wonder if you thought about the legality of  sending content over with the scene files. I think the comercial render farms aquired all the c3d content so they have a lot of the content that people use.  But if you do it with 'regular' users they may not have the right items.
I hope it works  - seems a worthwhile idea.

"I paint that which comes from the imagination or from dreams, or from an unconscious drive. I photograph the things that I do not wish to paint, the things which already have an existence."
Man Ray, modernist painter
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