As far as the composition goes, I would expand the drum sequence. Don't get me wrong, a simple "1,2,1,2" has it's uses but I think your composition could benefit greatly if you really paid attention to the drum work. I absolutely love the Vocalish flute sample you are using, as well as it's note sequence. I would keep that. The only other thing with regard to a composition context that I think might want to change is using only one note for the staccato string sections. Add more detail to it.
As far as the mixing goes, I would add a parametric EQ and lower the Mids a Tad on the master channel. I would also add bit more low end frequency to the kick drum, peppered in with just a tad of Mid increase.
OH! and p.s Make use of half time in your drum tracks. I cannot over express how the change in snare frequency can change the mood of a song. To give an example:
https://soundcloud.com/jacob-kauble/the-shattered Notice from the beginning of the song, the snare always hits on the "3 count". Meaning if you are counting 1,2,3,4, The snare would be hitting on the three. Then listen after 25 seconds in and you will hear the timing of the snare change. It adds a sort of "Breakdown" effect and can be VERY VERY usefull when scoring any type of drama.
Also,(and I promise this is the last one lol.) Minor, Minor, Minor. When scoring a battle sequence, make use of both Minor keys as well as diminished scales. The notes used in those keys gives a sense of struggle. Anyway, good luck to ya bud!