Oak is my base wood.
I use milder woods for longer smoke times (+8)and more intense woods for less smoke times.
I've played with hickory and mesquite smoked in apple juice/beer mixtures to lighten the "smokiness" on long smokes.
Experimenting with the smoker is one of my favorite things to do. Apple, cherry, maple...this list goes on and on.
For me:
Pork Shoulder = White Oak (well soaked)
Brisket = Oak/Mesquite (can be "too" smokey)
Chicken or Game Hens = LOVE Hickory/Mesquite mix with Apple Vinegar
For me, smoking is about trying different things and woods to find the perfect match for your tastes.
Some people brine, some marinate, some baste/mop...it's all good in my book.
Have Fun,
Drew