Hi, Dan.
Well written, sung and arranged.
I can easily hear the vocal the entire way through, and there's nothing
wrong with the mix. In fact, I like it a lot.
Now, what
I might play around with... that's a different matter.

How about doing a dryer version, without all that wonderfully lush reverb? In the beginning, you've got the fingerpicked guitar panned on both sides. You could instead start with the fingerpicked guitar on a single channel without the stereo effect.
Wait until the second verse to bring the guitar in stereo.
Take that huge reverb off your voice and place yourself into a room. You can have a touch of reverb, but aim at something that makes it sound like you're in a real location.
For the third verse, take out the guitars. They've already had their change to shine, and they aren't adding anything at this point. You're adding other things to the mix, and it's getting too busy. You need some rhythm, but something as simple as a shaker might do. You can back off on the reverb with the strings.
The low string bit is really nice, but giving it to a solo cello would be killer.
Then at 2:04 you can bring the guitars back in, and they'll be more than welcome.
At 2:38, you get the payoff for taking the reverb off your voice. With just the strummed vocal, the vocal becomes much more intimate and close - fitting the idea of a "simple song". I love how light the high strings are when they enter at 2:48.
At 3:12, the midrange string part is getting in the way. Too much reverb on everything. The high strings and horns on the bottom are enough.
I really like the ending.
Those are some thoughts, and worth less than you paid for them. Ask me at a different time and I'd probably say something else.
