Are you familiar with Deborah Silver who used to own Detroit Garden Works and writes the blog Dirt Simple? She does stunning containers for all seasons.

https://deborahsilver.com/blog/

If you can find ornamental kale or cabbage consider a combo with a center gathered tuft of branches that can stay for the winter arrangement.

Oh, yes, I do know Deborah Silver's work. Thanks for the inspiration! Good idea to start with a center tuft of branches that I can build on for winter.