My heart lept with joy when the girl playing bass drum switched from single-note technique to roll-technique with a traditional style handgrip. Same with the snare drummer's music being visually represented by changing the dynamic by moving from the center of the drum to near the rim after the initial hit. Even the vibration after the bells were stuck with the hammer while the pedal was depressed was spot on.

Then you look at stuff like each player's height being considered for the trombone cuts, keeping slide positions consistent with both the music and the animation, the way they bow and dip with the phrase shape of the music and their breathing... it's all outstanding.

Phenomenal attention to detail and idiomatic performance tendencies. Something musical of this caliber will likely never be replicated in the world of animation.