Not every piece has the same musical element in the foreground.
Gene Puerling – and Eric Whitacre – tend to put vertical harmony in the foreground. Alice Parker put melody in the foreground. Vulfpeck puts the groove in the foreground. For Maria Schneider, I think orchestration is a foreground element.
As a composer and arranger, I am certainly thinking about what elements I’m putting in the foreground as I write, but I’m thinking more as an interpreter. Part of the score study I do is in understanding the intent of the author, and especially what they think should be in the foreground. Then I can help my students bring that to the foreground, too. *
(We’re singing a Vulfpeck song right now in the Aces, and the focus on groove and feel is a real challenge for the ensemble. A delicious, welcome, important challenge!)
* this is a kind of straightforward study that anyone can do, even busy teachers who don’t have minutes in their day to use the bathroom, let alone study scores. I do most of my score study in 3-second bursts during rehearsal.