You've misunderstood kickstarter. It definitely doesn't have to be projects "that wouldn't get support from traditional funding channels". And they can be quit

You've misunderstood kickstarter. It definitely doesn't have to be projects "that wouldn't get support from traditional funding channels". And they can be quite strict about only allowing projects that are nearly complete. It's extremely common for a boardgame, or other project to be "complete" but need a tonne of investment for production, shipping, etc. Seems like the perfect model for a book launch. And the fans get what they want too with all the bonuses.