The thing that I liked most about this song was the atmospheric production. It felt very much like a lullaby, with the samples of rain, the heavy reverb on the piano and other instruments, and various assorted synths speckled throughout.
I liked the subtle use of vocoder-like vocals throughout the song, especially when they became more prominent at 1:03. However, I found the fast-singing section that followed that to be a bit disappointing--given that the piece as a whole is quite serene and ZipZipper's vocal style is very gentle and smooth, the rap-like cadence was sort of jarring.
Another aspect that kind of stood out to me in a negative way was the orchestral samples before the last section. It's difficult for me to say exactly why, but I felt like they contrasted too much with the sound set you had built up in the rest of the piece--in addition to the sudden change of tempo throwing me off.
In general, this song felt kind of lifeless. While there were a few nice chords in here (especially the last one--that was a great turnaround), I just didn't find the main progressions to be that interesting. And while the vocals are well-sung, they didn't sound very motivated. However, take this last bit of criticism with a grain of salt--I tend to prefer instrumental music in general. Certainly, this piece has some great, moody production throughout.