i love how the dissonances compliment the rising motion of the polish chorale leading up to the "gloria," and how you variate the "in excelsis" in sequence going to a third and then to a PAC of "deo"
the mashup between the two songs really works together
and i loooove the ending: the high violins repeating the "gloria" section (actually, they just switch up place with the violas and cellos from bar. 10 onwards), the highest register of the piece being used only at the very end, the harmony stays still and doesn't show any harsh dissonance except the one on bar 18 cellos, going chromatically from B-flat, B, and C for the final cadence, and finally, the end chord, I over IV, is just a nice tie over the whole thing
i let out a sigh
great piece dude !!!