Songwriting - From a songwriting perspective, I thought the tune was OK.   I enjoyed it, but found it a little predictable.  But it was certainly in line with the power ballad genre.
Production - Good job (although I'd can the whistling).  The production is right on target.  You did great with the equipment you have.  I think the strings sound fine.  You get a bit busy with them in some parts and that's where they sound midi-ish ... and, yeah, the piano sounds midi-ish too.    
Mix - I'm listening at work with headphones - so this review is biased as a result.   I think the mix is good.  No complaints (although I'm ignoring the distortion you warned about).   Vocal sounds good and sits nicely.
Let it Be - Ha !!   "Let It Be" is one of the few piano songs I can play as well.
I'll check out some of your other stuff tonight from home.
Enjoyed it.
BPOCO