"don't completely mesh for me with the synth-y strings"
I would agree with Dave on this.
In this type of song I would probably use individual string instruments, or a four part string patch to maintain the organic feel.
The attack of the string patch is also a little distracting in this rendition, somehow 'off'.
Singing is fine, right out front, but for me, when the strings were playing, it seemed like something was missing in the guitars. The left side finger picking seemed to disappear a bit.
Otherwise nice job.
Take with a teaspoon of salt; as Dave mentioned we will all have our own opinions.