Thank you for the reply. Given the time lag between your reply and when I had to prepare the meat, I moved forward with another recipe. However, after tasting the result and reviewing your suggestions, I will definitely move in your direction the next time.
After now looking at other postings, let me backtrack by stating I live in KC most of the year but spend the summer months in SW Michigan on an inland lake. We have a lot of family and friends visit (isn't that what a cottage is all about?), and a majority of the proteins are prepared outdoors on the grill given the size of the cottage. So, the addition of a smoker made great sense (and a wonderful birthday present).
I made a rub that had coffee grounds as the primary ingredient, and included some ancho chile and brown sugar, along with salt and pepper. Since I had pre-treated with hickory and loved the smell, I went with that. While it tasted fantastic and was tremendously juicy (I took it off at 148F), the rub was a bit bland and the hickory (as you stated), a bit strong. With the remaining rub, I will add more of every non-coffee ingredient. And, will definitely go with applewood next time.
You get your props, though. My wife did say her preference in the future was for the addition of a sweet component. There was not much in the way of drippings with these particular tenderloins, and the juiciness/tenderness were top-notch; what else would the use of the aluminum pan bring to the end result (besides a bit easier cleanup)?
Looking forward to learning a lot from this forum!