I believe the authors should get exactly the same type of protection I do on their livelihood. I get paid hourly, once I have completed an hour of work I will never be paid for that same hour again. Why should it be different for someone who makes something copyrighted? I am not able to obtain any future royalties on the ethernet cables I install today, and the end customer gets full control of them to do whatever they want. They will never have to compensate me further if they want to move them, re-terminate them, sell them, or put data signals accross them. Once I've installed them, and they've paid me, we're done and I no longer have any say whatsoever in what they do.
Authors created work for thousands of years before copyright was invented. I don't see them stopping even if copyright were to vanish altogether.
Under your scenario, the author would not be paid while not working on a book. Seems fair. But who exactly pays the author while he's working on a book? The consumer, who doesn't get anything until it's completed, or a publisher? A publisher certainly wouldn't have any incentive, since anyone else could publish the book without paying the author a cent once it's finished. That leaves the consumers, who may not want to spend money until they can have a product in hand, by which time in your scenario they would not have any obligation to pay the author, anyway.