its nice
for starters, i would put a pad with long notes in the intro to make it sound less plain. past 0:50 i feel like it is still an intro. it builds nicely before it, but then after it sounds like it should still build to something because it is "quiet", or "concealed".
Either after 0:50, or maybe 16 beats after something i would either build it to a more "open" melody for a chorus, maybe with another instrument with the main one.
Or maybe if you want it to stay more "ambient" i would have that part in the middle fade out a little and come back in. have variation to keep it interesting ;)
Also, if you notice, the intro is good in the beginning, but thats the ONLY time you hear the song like that. No outro, middle, anything uses that intro again. Maybe include that intro in the song somewhere. So thats another way to have more variation ;)
good luck. good work so far, not a bad start