Why would you have a whole note for the harp? It's not an instrument capable of being sustained (besides an open pluck, which makes no difference in the soundfont you're using), and a quarter note would work just as well. It actually doesn't matter though, I suppose. Although I would say it would sound better with ascending arpeggios there, maybe in Green Scale form.
Anyway, the song sounds pretty nifty. ~
The only real complaint I have is it sounds empty, but I guess that's just me. I think it'd be good to have some background woodwinds - definately an oboe, and a Bb clarinet would work well too. I can hear that fitting really well... yeah... staccato quarter and eighth notes, having the instruments splitting the chord.
LOL sorry, can't help but brainstorm when I critique. You're off to a good start IMO.