This was pretty well done all in all, the song was really chill and relaxing.
The scene selection was very well done, especially the beginning.
As for the transistions, I find it good it did not have hardcuts all the time but you decided on crossfading the clips at some times.
The only minor flaw that bothered me quite a bit was that at some points, I didn't think the video footage really matched the music. I think this is a rather sentimental anime, but yeah, that's the only thing there is.