From the Mark Lemley paper quoted elsewhere on this page:

Economic theory offers no justification for awarding creators anything beyond what is necessary to recover their average fixed costs.

I think I'm fairly happy putting my faith in him knowing how economics works.

I think, contrary to your suggestion, that plenty of people are already fed up with the same old movie sequels and annual releases by the same computer game franchises and so on. But that's what happens when the system doesn't effectively support those who would create more interesting alternatives, which typically aren't as profitable on a first outing but cost more to produce. Coming soon: Cloned Sports Franchise 2013 edition, with ads shown every five minutes during your favourite fly-on-the-wall reality TV show.

Do you think Notch would have problems raising funding on Kickstarter? How about Quentin Tarantino? How about Amanda Palmer, of the Dresden Dolls? How about the XX? Stuff which has a cult following seems to fare well under the patronage model.

Most of the really high budget stuff turns out to be fairly derivative. There are exceptions, but they're rare.