Yeah, I also felt it was both a bit General Midi'ish, and also a bit tight.
I started out with a GM sound module + a Juno106 and Miggy samples. It can be pretty tough pulling rich sounds from GM.
I think the music could benefit from looser, more natural timing, and probably a bit more harmonisation in melodies. Harmonies can help to add richness, and character, which may not be present from single tone sounds. Chord progressions, rather than single tone melodies, and harmonic cadences, can both give a lot of character.
Hope this isn't more feedback than you were looking for.