Tempo changes feel a little unnecessary at times - maybe it's mostly the rits (slow downs) that feel strange and too long and too extreme - try your best to make these feel like a natural slowing down - imagine a conductor in this situation - at the moment it sounds like a straight line in tempo automation. Violins might sound better with staccato patches when they're playing those arpeggios about 1/4 of the way through.
I'd generally work on articulation and a really close attention to detail - there's lots of times when the patches reveal themselves to be not real. It takes a lot lot lot lot lot of work to iron out every possible clue that might call the orchestral instrument's artifice to attention but it's worth it in the end : )
Another thing is not to mix with the faders too much, try and think about the real capabilities of the different orchestral instruments in relation to one another. I hear drums that I can tell are just turned down on the fader and pizzicato strings that I can tell are just turned up on the fader. This creates an unnatural sound. Thing about it in the context of an orchestra - if you want the drums to be quiet, perhaps don't have big war drums just turned down on the faders, swap it for a tambourine or just a snare. I think that's really the key to mixing orchestral mock-up type tracks. If you want loud pizzicato, think about how you would achieve that with an orchestra- you would write forte but that wouldn't make it as loud as it is in comparison to the rest of the stuff now. You might want to double with pizzicato with staccato woodwinds or make the rest of the orchestra more delicate to let the pizzicato strings take more prominence.
The composition itself is good but a little on the generic side for my tastes. The guitar section was cool and unexpected. I'd strive for more changes of key, really strong melodies that re-appear in lots of different contexts, a more clear structure full of direction, a nice change of time signature when appropriate, a little more unique and playful orchestration.
Although, about the structure - I think part of the reason it sounds a bit "this section then this section then section" is as you've said before this is a kinda pass-the-parcel type collab with another person right?
Anyway, as has been said before, you've passed the bar in terms of the standard of the production and the composition but there's still more you can do to really excel.
Good job and good luck! : )
Edited by Calum Bowen, 04 February 2013 - 08:54 AM.