I was listening to Johnfn's songs from ngadm 2013 because I randomly remembered some of his melodies and then I decided to listen to Steampianist's songs as well. Then I saw your reviews and decided to listen to your music. I know this is a very late review, but I want to get better at critiquing music.
The main melody is so catchy! Although the melodies are predictable, they still sound beautiful and cheerful. There isn't a single melody I dislike. I like the note change at 2:51; I did not expect that at all and it does a good job contrasting the most common chord. The tempo change transition is interesting; I never thought about doing that before and I will try it if I can remember. It sounds like the piano's reverb isn't constant throughout the song. I'm guessing you added reverb when the piano was alone. The mix doesn't sound good at 4:51, but this is my favorite part of the song because I love when piano and strings are played simultaneously. Besides for the mixing problems, which I know you didn't have enough time to fix, I only have one complaint: Although the piano itself sounds good, the positioning of its melodic notes sounds too perfect.
This is one of my new favorite songs!