As a native, I feel almost disloyal saying this, but California should keep its primary precisely where it is. This is a 35,000,000 person, 158,000 square mile state. There's no way, within the context of the early-primary rush, for Democrats to seriously, thoughtfully, or comprehensively campaign within it. All they can do is spend money and rely on name recognition making it a competition between the famed and the funded. And that doesn't mean we'll just have a primary entrenching the likeliest outcomes: It means we're going to ensure those outcomes. Any minor candidate seeking to remain even marginally competitive will exhaust their coffers in the first ad run through the Los Angeles media market.
As it stands, I don't like our primary system, or our funding system, or the lineup of states that choose the nominee, or New Hampshire's crackpot insistence on going first. But the one thing I do respect about the current set-up is its vulnerability to new voices, voices that would be easily drowned out by California's cacophonous media sphere and culture.