The melodies sound fine. The extreme volume differences make it kind of hard to listen to. Dynamic range is okay to have, but I'm having a hard time listening to it in a loud environment. Mixing, along with all parts of music production, factor in to the quality of the music. Make sure to keep working on everything. The song started to get a little repetitive, too.
Thanks for the review! The main issue I've been having is the big differences in the song between .wav, which I wrote and mixed it in (and which NG doesn't take) and .mp3; trust me, it sounds much better in its original form. About the repetition; next time I do a big overhaul on this piece I'll hopefully have a vocalist which will make the song's structure a little more ear-pleasing.
Please contact me if you would like to use this in a project. We can discuss the details.