Before I start I'm going to say I'm not an expert so take whatever I say with a grain of salt.
I think the idea in this track is really good, the melody sounds great and works together with the chords to create that uplifting triumphant feeling, and the harmony parts on the violin sound great. However, the orchestration feels really thin to me, and I think this is because the elements in the mid-low to low section (Cellos, Double Basses, Bass Trombones, etc.) of your track are a lot quieter than the violins and higher brass parts. These low elements are what make a track sound full and big, so I think your track would greatly benefit from some more prominent low elements (Just make sure they don't overpower the instruments carrying the melody). On a positive note, I really liked the countermelodies in the high brass section, and the key change at 4:47.