Wow, it sounds very good. It flows nice and has a happy, yet sad feeling to it.

As far as improving it, it depends on what your trying to do with this. It would be awesome intro or outro music to anything from a Video game to a movie. Even to an album. Though I dont see it much as a single track, just because its music that creats mood. Kinda hard to explain.

It doesnt sound ripped off at all to me. Not exactly 100% original, but by no means ripped off.

Good composition.