Being non-commercial is never an ambition. Movies come together at different points for fortuitous reasons. You do them as you get the opportunity, as opposed to doing them when you choose to or design to.
Like any kind of writing, there are good days and frustrating days. But even frustrating days can be rewarding sometimes.
It's more interesting for me as an audience member to see a movie about a loser.
We tend to do period stuff because it helps make it one step removed from boring everyday reality.
When the movie's done, you talk about either the score or source music over a particular scene, what might work. You just throw a piece of music over the scene, and we both listen to it.