Interesting question, Evan. My family and I lived in Alabama for six years. I had several mature crepes in our gardens. They were gorgeous. I occasionally did some light pruning. I had no trouble with suckering, but then I didn't top them or chop them down within an inch of their lives either.
Crepes are truly a tree/shrub for every season. Not only do they have gorgeous crepy flowers, they have beautiful exfoliating bark which reveals lovely markings, as if someone had come along with a paint-by-numbers kit and decorated the trunk in colors ranging from cream to warm beige and cinnamon. In fall the leaves turn shades of red and gold before they drop, and in winter the limb and trunk markings really stand out.
Exfoliated branches
Fall colors
When we moved back to Iowa (zone 5) from Alabama, I brought this crepe myrtle home with me. I potted it up and for many years moved it into an unheated room in the basement during the winter and lugged it back outside in the spring.
An ice storm in late fall, before I moved the pot to the basement