If there was a PSX version of Megaman 9, this would fit nicely. I do however have some comments.
The volume increases suddenly, then gets softer, then go backs up again. Whether you meant for that or not, it didn't do it for me.
Another thing that bothered me. It's the main melody. It should be louder. It should come out of the song and be heard. I heard no significant change of volume there.
You did a good job though. It's nice.