As I see it - The base elements are there, but you should work on equalizing the song (as in making sure there's enough bass, that one instrument doesn't drown out the rest, etc).
One thing you could do is have the same sound (for example your synth), just an octave or two lower, and quieter. It would add more body to some of the thinner sounds.
In any case, with some tweaks this would make good videogame music.
Also, your on-screen karaoke was a bit hard to follow