The first thing that came to mind, was that you could basically lose the first minute and a half of the song. It's droning in a bad way without building up to anything. All you really need is about 15 seconds or so to establish the beat that's going to used throughout much of the mix, and then let the melody of the original song come in (the part around 1:45).
I'm also not too sure about the whole fade in/fade out of the choral sample. It starts feeling like the bass of the drum is too much for something to handle, and acts more like a defect in the mixing than a purposefully chosen effect at times. Maybe that's what you were after, but it feels... off. Perhaps something else to vary up the choral part? Different effects? Having it get cut off rhythmically during the sample's playing?
Might I also suggest more of a build up for the second half of the song? It hits a certain point earlier in the mix (around the 3:10 point), and never gets built any higher. For the final time the beat, melody and such play after the 4:30 mark, it feels like it should be going all out, but it isn't. It's just a repeat of the previous time it all played. Try making it fuller sounding in that area with new instruments that you could tease the listener with earlier in the song (small sections where it plays here and there, etc.), then full on assault them with everything for final time through before the quiet ending plays.
It's not a bad start, it's just too long for it's own good and could use some trimming. And I think with one a final step up in fullness and sound on that last melody/beat play through, it would help push the mix further.
Anyway, those are my thoughts. Take them or leave them as you see fit.