1. Don't listen to these cunts, this has potential.
2. This could be more than just some stupid little diddy for a videogame, you could turn this into, I dunno, a real piano and string quartet piece.
3. Space is good, don't let anyone tell you otherwise.
4. I like the time signature changes, it goes well with the space. If melodies and shit were flying all over the place and making the piece complicated, then yeah, they wouldn't work, but the direction I think you should take this is a very laid-back, almost free-tempo piece. It works well as 3 bars of 4/4, and then a bar or 3/4 (or 6/8).
5. The melody is a little stock, but some people try way too hard to be original with melodies. Work with it a little, but not too hard to make it different. If you can't seem to get anywhere, try the other route; making everything else interesting. Like the chords that play underneath, or add some flare with echoes or other things. Add another melody to compliment it, but make it stand back a little, taking a back-seat to the original melody, if you will.
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