Hi, Dennis!
I don't remember which method you use for ribs (3-2-1 or variation), or straight smoke. If you do foil, you can try OJ for the brase. I've used blends of OJ as well, with Lemon, Lime and others. It adds just a hint of the juice flavors...I like the method because it's so easy, but we like that little extra flavor too. You could also do a concentrated juice by reducing it in a sauce pan, then misting your ribs with it if you don't foil.
Another idea you could try, is zesting an Orange, drying the zest, and adding it to your dry rub. I've used Lemon zest a couple of times and that put some zip in the flavor...very good.
For smoke wood, I'm limited to what I can buy, so Cherry, Mesquite and Hickory for the most part. Cherry, if you have it, is really nice with pork/poultry...I generally go with Mesquite for pork. Alot of others here have Oak, Maple, etc. The smoke wood type is probably not as important as how you use it...thin & blue as always.
Let us know what you try and how it works out for you.
Eric