I like this approach as well. I find a session 0 often gets players pumped for the following week. Also, taking some time with character creation to establish ties and hooks just makes the game better.
On the other hand, sometimes players with a sketchy or no background develop into the deepest characters, and others who arrive with a novella don't actually play to what was written. One of the longest and best campaigns we had was thrown together quickly. We were just going to use the characters for quickie, more shallow adventures as a break from our more "serious" group. They took over....The campaign was long, detailed, not at all shallow. We were planning on using published modules and adventures from Dragon magazine. I think we used two. The characters clicked, stories took off. It's still remembered fondly, and that was about 14 years ago.
That's what I love about this hobby. You never know how things will unfold.