Cool
Whether or not this was your intent, you made an 8-bit video game song :P
I'm impressed at how full this sounds, given that I can only detect one patch in the entire song, used as both bass and treble. I'm glad to see that there is no random clicking and that you take the time to adjust the stuff on the screen to fit the melody you're thinking of.
You're probably not going to improve on this song; I know I don't like to change and resubmit songs. Either way, some parts of this could do with a nice atmospheric pad.
Knowing that you have talent, I suggest you experiment a lot with yor audio programs to find out all they can do. Talent may be innate, but the only way to get technically good is to practice.
I'm sorry if I take a teacher-like tone, but I'll hazard you haven't made a whole slew of songs before this one. Take this all as friendly advice.
-synteza-