Forgive me for saying so, Lirin, because obviously it's hard not to take that sort of criticism a little personally—but you have no basis to say there's something wrong with the mastering. You can say that the mastering is different than how you would do it personally, or different than you would expect, but saying that there is something wrong with it suggests that there is an objective "right" way to master a soundtrack—which there is not.
If I understand what you're commenting on, though, it's interesting that you use the phrase "not natural"—since I think what you're picking up on is the fact that this album has more of a concert hall feel, whereas most movie scores remove any sense that the music is being played in any sort of real space, and simply put it right up in front of your face. Of the two, I'd actually say that the latter is less realistic.
Just my thoughts—but again, I'm pretty biased. Also, we didn't quite have a big enough budget to hire Hans Zimmer, so comparing our soundtrack to a Hollywood score might be a bit unfair in the first place...
