Seinfeld Isn’t About Nothing
…you mentioned Cellar being largely about nothing, and I that comes from Seinfeld, though I think there’s an important distinction. Seinfeld was about it’s characters devoting an inordinate amount of time and energy towards weird and neurotic pursuits, making mountains out of molehills. An entire half of an episode devoted to Jerry returning a piece of clothing ‘out of spite.’ But that idea is actually pretty brilliant, and it’s something we can all relate to, not because we’ve done that specific thing necessarily, but because we all have our weird things that we spend a lot of time/energy on that most people don’t.
So, if we go into Cellar without any specific ideas or quirks for the characters, and just tell the actors to improv based on very vague and loose direction, then we will film a few hours of improv and hope to get 30 minutes of good and connected footage. That may work but I think its better to come up with stronger character ideas first and leave less to chance.