This was the largest ensemble I had ever written for. I wanted to give the chorus plenty to chew on, but also include time to feature the piano. So, the arrangement features a pretty traditional opening chorus, then a piano solo (including the chorus in an accompanimental role), a bridge where the chorus breaks out of the standard 32-bar form and develops the melody, and finally a return to the head to close the arrangement.
The collaborative pianist, Ben Tibbetts, is an improviser as well - but I didn't know that at the time, so his solo is written out. He played beautifully, adapting nicely to my somewhat limited understanding of the instrument, and adding some nice flourishes to my written score throughout.
Choral singing is really antithetical to jazz, in several ways. Most concerning is the "attack" of each note. In jazz, it's typically a sharp, percussive attack. Choral singers have a more gradual attack. I was lucky enough to have some rehearsal time with the chorus, where I talked through this challenge, and they adapted really well.
Personally, I'm happiest about the "development" section of this arrangement, the part where the chorus comes back in after the piano solo. One little moment to listen for there is the altos in MM 126-128, "you have me all the same". Greg, who knows my music as well as anyone, called this out as the most "Mark Abbott moment" in the arrangement, which I took as shorthand for "hardest to get the chorus to sing", but I do think it's really typical of my writing so it always sticks out to me.
Thanks to the chorus, and to Greg for his thoughtful direction of the arrangement.