This piece has a lot going for it. nice work. I'll only address the mix, which is good, with good balance and separation of instruments, both in panning and depth. I guess there are a couple of ways to address dynamics. One is the terraced approach where you add more instruments to a section when you want it louder, as opposed to just adding volume to what's already there. And you've done this well too. I think it's necessary to be obvious with this because subtleties don't always come through in MIDI mockups. However, that doesn't mean that you don't need the subtleties. I'm referring to volume swells within each line with CC11. Do this a lot! It will make a big difference in enjoyment. Are you familiar with Wendy Carlos' music? an early pioneer of electronic music. She said, regarding expression in synthesizers, "Everything that can be controlled, must be controlled."