Nice song
Soft and smooth ambient song. Though the occupation of the space is definitely here, and even a bit too pronounced maybe. So it sometimes sounds a bit too chaotic cause of the superposition of all your long notes, the reverb and the succession of accords at piano.
Next to that, the main issue is on the brutality of the chaining of all the different cells. It's each time really sudden. Even in the very beginning at 0:16, your ascent is cut as if it was shot down in its race. Think about adding a lil cymbal or something like that to the arrival. I'm sure some nice soft percussion transitions would make a great effect and prepare for your next melodic line.
A last thing I didn't really like or understood is the acceleration in the end, I guess you changed your tempo at 1:08, and like the rest, a bit too suddenly ;)
So, finally, I really liked this little song, melodic and apeasing (even if it doesn't lack of rhythms), particularly the very beginning which is really the best part in my opinion. Anyway, nice melodies, nice arrangements and accompagnement, a good variety through all the song (which doesn't need to be extended in my opinion, it's really good as it is).
Good job ! (and forgive my bad english)