Great Sound
My one piece of advice is that you think too much about melody and chord (bassline) and the sound but you lack on complexity. Your percussion part is repetitive and plays beats. It also uses only standard equipment. Try something new, like vibraphone or chimes or timpani.
Your harmody is also pretty simple pitchwise. I hear a lot of single repeating notes. (starting at 1:00). This type of repetition is not good, it is wasted creative space.
You also have a few too many places where different instruments playing in unison to each other. (i enjoy 2:00+ a lot). Add voices that play different things. It just seems very melody and harmony only and sounds simplistic that way.
On the other hand, I can tell you did a lot of work and its not actually all that simple. (I compose also). Your mix of sounds is good and your extra additions to the melodies are great, but you simply spent too much energy worrying about sound and not to complexity.
5/5