As Arsonist said, this is really the definition of an epic piece :). The instruments mix very well together, and this almost sounds like it was recorded live.
One thing I want to point out though, is that the mixing of each individual instrument could have been done better to make them simply sound a bit better. Especially the horns had some frequencies that really anoyed my ears. Try listening to the instruments and identify the frequencies that sound good and the ones that sound bad, and cut or lower the bad frequencies.

-Ectisity
{Review Request club}

This is straight up epic. I can't even tell what wasn't live recorded. This is super good and you should keep it up!