I have used my share of rubs, to me they are like clothes, today's fad mostly. Oh I have had some that really turned my head at the time but after a bit they usually all get filed away in a large packing container in the garage. You know you'll like 'em all again if and when ya get around to it. Then the new fade hits and its good so the cycle repeats itself.
After so many times, I find that simple is good, it accents the meat, and that walk to the packing container in the garage, seems too far usually late night when I think about rubbing something down. You'd be amazed at what a simple salt and pepper will do for meats.
It may just be an age thing but, seems with most I know as you age the simple things done well seem to be much better than the new fad items.
I seem to lean these days to a minimalistic approach. I mean I am sure that coffee wood would make a great smoke, but I know I like pecan. If I spice up a rub its garlic or onion or chili's, or currently I do like some Tontaka Dust on my steaks! But its a seasoning salt, not really a rub IMHO.