What makes a great BBQ experience?

I am in mobile food service - mostly weekend warrior stuff. For the last two years I have been using a wood fired oven to cook and serve pizza. Last week, I sold my oven in anticipation of soon being able to move into a fixed location. Until that happens, I will be serving BBQ.
 
My pizza was always an opportunity to give customers a unique and wonderful culinary experience. They loved it and were never slow about letting me know. As I transition - temporary or otherwise - into BBQ, I want to be able to provide that same culinary experience. My question to you, a great community of individuals with great ideas is this:
 
What makes a great BBQ experience? What menu items? What tastes? What makes you say, "Wow!" in BBQ, in either a mobile environment or in a fixed location?
 
Thanks in advance!