I'm with Mark here - the vocal is what sells the song, and so as long as the arrangement supports the vocal, it's a success.
As other noted, the vocal is indistinct in places. I'd like to have had it closer in front, but it fits the mood.
The cajon seems off-beat in some places, and is so quiet, it doesn't really seem to be adding to the mix.
Still, very musical and kept my interest throughout.