The Heaviest Burden (guitar-based piece for a short film)

Hello everyone, 

A friend of mine has made a short film and asked me to try to make some music for the last scene and the credits. He wanted it all played with real instruments so I had to work with what I had, a cheap classical guitar and an digital piano. There was not much time left so during a couple of days I tried to compose and record an initial draft for the piece. I might have in a week a few chances to record the sounds again and modify the piece so I was wondering if anyone had some feedback about the piece. It is my first time composing in such a style and with real instruments (I mixed it all in Reaper) so I am not sure about the result. 

The instruments are: 2 classical guitars, piano, electronic dark pad, electric bass (the electric bass is also played in the piano). 

The piece is based on a 8-bar harmonic progression which could be understood as: Am9(no5) - Am9(no5) - Am9(no5) - Am9(no5) - F#4 (add6) - E7 - F#4(add6) - E7/G# (However, when the electronic pad enters, I harmonized the Am9 alternatively as an Am9 and a Bdim7 chord in the pad voices taking advantage of the lack of the fifth in the strings). At 1:30 the credits start so there is change in texture and the melody becomes improvised before playing the main theme once more and then the ending of the chord progression at the same time that the credits are ending. 

The piece is called "The Heaviest Burden", a reference to Milan Kundera's "The Unbearable Lightness of Being", since the last scene of the short film reminds me to the ideas found in that book. The piece is supposed to be melancholic/nostalgic but with a little bit of hope.

I recorded the guitars with my mobile phone and the rest directly from the digital piano sound exporting function. Really cheap guitar with years-old strings and no nails in my fingers so the sound is really dark and hollow. It all sounded as a toy at first but I think the reverb made a really impressive job for making everything sound better.  The idea is to re-record the parts with a nice mic and new strings, but I am not sure yet about whether we will have time to do it or whether we will leave it as it is.

Any feedback about the piece, whether you think it works or not, or how it could be improved, is more than welcome! Thank you!