I try to stick to my values and principles as much as I can.
I deeply value most of my work, most of the time, and feel very lucky that I'm doing what
seems to be the thing I'm best at. Like Max, we studied together at art school,
my background is scientific (chemistry) and felt liberated during my new studies.
I was very dogmatic at that time and didn't want anything to do with stuff I didn't
value as much as other stuff (like commercials).
Nevertheless, working in sound(-art) doesn't always mean that you can choose.
I found that out later in my career :) I'd love to work a bit more in documentary,
than in fiction, but I take on what is available and pays the bills.
The media type doesn't matter to me all that much (whether movie, documentary,theatre, online, museum or sound-art).
I am open to new ideas and philosophies in daily life and that flows through my work also. Most important to me is the kind of people running the show. I really have to 'like' the director and feel challenged by his/her story, otherwise it won't work very well for me.
Advertisement, like I described above was a great example of what was not my cup of tea.
Making personal sound-art is something I try to do as much as possible and is closest
to the idea of living/working by my values. But this is mostly unpaid or severely underpaid
work that I do for my own satisfaction. Kind of like a hobby, which was the trigger that
got me into the world of sound.
after your edit the question is a bit clearer.
What makes my work more valuable: knowing that my contribution will help tell a story i 'support' will find a bigger audience. And hopefully in the same process show the audience that sound is a storyteller just as much as the visual part of the medium in play.
Things I turn down: stories not worth telling (in my humble opinion) or in need of a better storyteller than the person in charge. or better said, projects by people on a different level of skill/experience/philosophy, and this could also mean that I'm not fit for the job. All in good times :)