Jeff,
You can get plenty of bark in a CS, my thought would be if there wasn't a little sugar in the rub, then you'll only get a little bark from the actual smoke itself.
Take a 50% to 50% mix of rub to turbinado sugar (also called sugar in the raw). It's granular like kosher salt and last a little longer. Brown sugar is okay, but for me, it darkens too much.