There is a reason why I settled on 6 as being an optimal number for my writing. Simply put, when I write for an odd number of horns it seems to me that the middle line is boxed in by the lines on either side. I especially have this feeling when I do linear writing with contrary motion for 5 horns. Of course, I cross lines and use other techniques to give an interesting part to the middle horn player. Nevertheless, I have a hard time coming to grips with that middle line. When I began to explore what I can do with 6 horns everything came together. There was no longer a middle line! And, with 6 horns I can do the kind of writing that I like for larger ensembles.
I am sure that at some point I will feel inspired to do more writing for 5 horns or even for big band again. However, for now, I am experiencing an exciting flow of creative energy in writing for 6.