Dave, you're encountering the hardest part of converting from a "traditional" smoker to one of these - breaking old habits. Many of the techniques you are used to are intended to counter the effects of a charcoal or stick burner (namely moisture loss). Those smokers are a much drier environment, and all the foiling/mopping/spritzing/putting in pans, etc. is to keep the meat more moist. What you'll find, with these smokers, is is just isn't necessary. With most smokes, there is not need for au jus because the meat is already so dang moist! I don't think there would be any problem using something like a mini-loaf pan, on a shelf close below the meat, but I wouldn't go any larger. Drip pans between the smoke box and the meat have proven problematic, and are just best avoided.
Embrace the world of Lazy Q, and your old smokers will get lonely!