Very interesting piece!
I also had lots of fun using uncommon instruments in my composition of the last year's NGUAC finals.
The instrumentation is quite good here. Even though you were working with the same mode (D-minor) within the entire track, it stayed interesting until the end. It's rather hard to define the several instruments - I'm not so much into knowing every medieval instrument, haha.
But still, you have been using the instruments very well.
I also like the instruments positioning!
Some suggestions for improvement:
- There could be another drum - a big one (a taiko for example), to cover up the very low frequencies of the piece at times.
- The soundtrack sounds rather... mystical. I would have used more reverb here to gain that feeling.
Good job! :)