Moment Musical No.1 in A Minor for Piano

Hello everyone!

This weekend I experimented with a really simple atonal technique and I turned the experiment into this piece for piano.
The technique is "mirror writing". I applied it in the simplest way possible. The process was the following:
1. I decided on using four voices and mirror them around the middle C axis.
2. For each melody note, I added the mirrored bass below it (for example, a top note A is accompanied by the bass Eb, both a major sixth above/below middle C).
3. After that, I chose both internal notes (considering that those need to also be mirrored against each other).

Except for two measures, the whole main theme was created through that technique.
Afterwards I composed a tonal middle section and turned the piece into the form ABA'B'A''.

This time I tried avoiding excessive exact repetition (with techniques such as changing octaves, creating different melodic contours and accompaniment, or mixing final restatement of main theme with the coda) in order to add some variety to the whole.
That is because I tend to just copy and paste most of my sections and I want to get rid of that habit.
In addition, the first measure copies the beginning of Schubert's Impromptu No.1 in C minor.

As always, every feedback, comment or suggestion is more than welcome and hope you enjoy it! Thank you!

PD: My main concerns are in m.39~40, where I change the ending of main theme making it maybe too dissonant, and the fact that the first time that I introduce the B section (m.13) I do not use the continuous tresillo accompaniment. 

Edited 3 minutes ago3 min by JorgeDavid

I like it, it seems to work! Some "rich" chords, but contrasting sections give the ear a break. The first theme briefly restated, end. Beautiful! And tasteful, not a wasted note. When I first glanced at the score, my inner ear didn't want to accept the A natural/E natural against Eb, Ab, but you make it work.

Edited 1 hour ago1 hr by Churchcantor