Do I know anything about existential butterflying? I don't know about existential! My version of butterflying has been to flit about the Americas doing strange jobs and meeting fine people. I haven't really worked a real job in years - only freelance and part time. Like you, I've ventured into many of the arts with great enthusiasm and had lots of fun, moderate success and a bit of heartbreak.
Somehow, there's been time. If I had too much free time I'd be doing it all--rather than focusing on one thing and savoring it. Of course when I'm writing I miss the music and when I'm playing I miss the theatre and when I'm teching I miss the crafts blahblahblah - so I take it a little at a time.
The best part is being able to enjoy them vicariously. One long-time friend is an amazing composer/musician and we talk shop a lot. I love to talk to and read the work of fine writers such as your self, and pop down to Memphis once a year for a theater fix. In a way, I'm living it all - all of the time. My days of crazy seem to be mainly behind me, which is no small blessing.
Basically what still eludes me is a sense of self-worth - a strong enough faith in myself to go the distance, at least with writing. Perhaps, because I wasn't as ego-invested in them, music and crafts were easier to present to the public. Therefore, it was possible for me to support myself through both, although hardly in grand style. Now that I have focused on writing, I find myself filled with doubt at the very thought of submitting work to publishers. My latest solution to this problem is to enter my work in a number of competitions. It's not ideal, but it's a start.
What I love about writing is chasing my elusive characters through their particular and often peculiar realities. I am amazed by the unexpected twists and turns they take, always away from my initial ideas about them and expectations for them. Gertrude Stein once talked about the inevitability of an author's knowledge of a character - even unconscious knowledge - effecting the reader's perception of the character, even if it was never written in.
Because I know that Charles Whittiker's lover is his cousin and therefore name him Whit, the reader will, on some level, also sense this - or something very closely akin to it! I chase these elusive clues throughout my own writing and the writing of others. Of course all of this is to say that my writing is character, rather than plot driven. Next to Jerry Seinfeld I am probably the queen of the anti-plot! But I'm working on that.
Once I have a vague understanding of my characters I try to put them into more interesting situations. And once I have a vague understanding of myself - I will try to present you with a more interesting article!