Very basic
Seriously, there's so little to this track, I can't really come to terms with where things need to change. Let's start with adding some voices and perhaps some variation in the middle, because it gets very boring after a few loops of this same piece.
Finally, when it comes to mastering, perhaps you could consider losing the first 10 seconds, as it's basically just silence, leading into the rain. Bring the rain in sooner, have it a little louder, so people can hear it and leave it for a few seconds, before launching into the loops.
[Review Request Club]