Soaking chunks does nothing but cause Dirty smoke - soak a chunk for 48 hrs and cut it in half - water only penetrates 1/8" or so. Soaking does NOT help.
Pecan and Fruit Woods are Mild. Oak n Hickory and expect Mesquite give stronger smoke smell/taste.
Wood burns Hotter than Charcoal so with more chunks your UDS will run Hotter - Let it within reason. I like 275*-300* for everything BBQ. I mix my chunks throughout charcoal . I could cook identical prepped meats on my UDS and my stickburner and you wouldn't be able to tell which is which with a taste test.