Ok. I see your problem.
Everything I thought about the mixed and mastered track, I now hear just fine on the original. What he did had no bottom and sounded like his ears were fried or his system is too bottom heavy so he over compensated with the midrange. Your mix sounds perfect.
Here's what I do when someone sends me a master to listen to. I first pull up a classical symphony piece that starts somewhere in the middle so I can set my volume levels to my speakers. That way I can tell that I am hearing everything I should without adjusting the volume for the piece. His work sucked.
Now for your work. I have no idea why you would call in all those great symphony musicians and then tack a pissy little drum machine into the mix. (I know, you didn't really hire anyone, but that was the sound you were going for.) Get a real drummer to come in and work on the drum tracks either with a drum set or a good drum machine and a selection of better sounds. If a crappy sound was what you were going for, have a drummer play on chunks of metal and wood to make those sounds come alive. And I hate that sound of a little girl spitting. Is that the snare? DUDE!
Now to the arrangement. This a arrangement by layering. That's not arranging. It sounds like a video game score. If that is what you wanted, then it is fine. Otherwise, try stepping it up somewhere in the middle about one step. If it is in A, move it up to B at some point. I'm assuming you also recorded midi as you entered the tracks. I think your ears are a lot better than your mastering engineer's. Don't ever use them again. And this is a good lesson in why having the equipment doesn't make them an engineer. Good luck.
Rod Norman