Do you have any interest in digging up the Brugmansia in the fall? I had so much luck with that method. I would just dig it into a pot in the fall and keep it in the garage until spring. Even if you find a hardy Brugmansia, it would spend most of the season growing back to a height where it can bloom. If you overwinter it, you'll get a flush of blooms in early summer and continuous blooms late summer to fall on mature plants.
If you try it in the ground, let us know how it goes! It would be great to hear the success story. Cannas and elephant ears are a great dieback if you're looking for some more height and color also. My cannas come back in NY, but sometimes the clump returns smaller in cold years. I haven't had luck with elephant ears outdoors, but I haven't tried the hardy cultivars.