Very cool song and vibe. The production I think is very thoughtful and the vocal is a definite stand-out. Vocally like the Samples, a favorite of mine, or even the EAGLES! with a violin, and a really cool fiddle part it is.
I also would call out the bass, not for being in tune (those low instruments are harder to tell about tuning but it sounds pretty ok to me tuning wise) but for the processing of it - I hear more "bass processing" than the actual bass. So it sounds super thick down there maybe? How did you process the bass? I can't hear any string sounds . . . it's like you have boosted a narrow band of it. Or maybe it's because the entire song is 90% just one particular bass note? If you are ok with the processing I'd take it down in the mix a little. But I'd be tempted to roll the processing back and add back in some selective mids back to that bass, just to hear it more organically which might suit the rest of your piece.
At 2:48 you are penalized 15 yards for gratuitous yet awesome guitar solo work. I spilled my beer. :)
cheers, cool tune!
-Tom