Your creation doesn’t need to have everything. Just make what’s necessary, and then stop.
I finished a vocal jazz arrangement today that fits on two pages. Not an a cappella ballad, either!
In this case, I was casting around, trying to see what kind of soli, shout chorus, vocalese, or other extension to the arrangement made sense, when I realized – none of those! There are pretty standard ways to write a vocal jazz arrangement, but they aren’t always necessary.
I wrote the head arrangement, marked “2nd time, open soloing” and when the vocals would reenter, and added just 4 bars at the end to conclude the arrangement. It’s the shortest and simplest arrangement I’ve written in a long time.
And it reminded me that a creation doesn’t need to have everything. It needs what it needs, and then you’re done.