I like the intro and I like how you have a sort of faux starting of the piece at 0:18 and then really kick things of at 0:27. The guitar that enters at 0:35 however sounds a little out of tune to me, might just be the choice of notes and the playing but it sounds pretty dissonant. The mixing is interesting, everything sounds very clear but the placing of instruments seems to switch around a lot. At times the drums are too quiet but at times too loud.
You can certainly tell it was improvised because the melodies are all a bit random and few seem to lead anywhere plus the playing is sloppy. The instrumentation is nice and full which i like but at times it seems a little crowded, again, that might just be the mixing. Nice chill atmosphere and interesting enough to keep me entertained for the full 5 minutes. Interesting ending.
In fact I sort of wish there had been more breakdowns and reversing/glitching throughout the piece. The structure is a little flat between the intro and outro. I think if you planned a piece out you could create something really great. Enjoyable regardless!