Actually I did imagine it as a video game piece. And I agree with your statement about the chord progression flow. I felt very iffy about it especially at the end when I was trying to resolve the piece within the 21 measures. The first few chords I had written down a few months ago and I came back to it to see if I could make something out of it.
Though it may be my first piece, and even though I'm not a piano player, I often try out different chords on the piano so that I can get an idea of what they sound like, which I think helped alot in writing this. Even though I know a good deal about part writing, I have to admit I kind of ignored what I know in writing this and I pretty much wrote whatever just came to mind. It was fun!
Thanks for the comments. This is a beautiful art that I am excited to get into.