Popum,
Congrats on a successful pork butt. It seems like most everyone new to the CS has a difficult time believing that all you need to smoke a 5-7 lb. butt is 2-3 ounces of wood. The brain just won't accept that so little wood can do the trick.
It is also interesting that so many people trip over the issue of the temp fluctuations. But if you think about it, a 50-60 degree temp swing with low temps (for chefs, anything below 350 degrees is considered low & slow) is insignificant because you are going for the long cooking time intentionally. That much of a temp swing in a 400 degree oven might be a little more of an issue because the cooking times are so much faster. Even with the oven in your house, if you monitored it, will have a 40-50 degree swing.
Bottom line is, the CS is very efficient at doing its job. It just takes us operators a little practice to get used to it.
Also, keep notes on your smokes. That way, if you have a problem, you can get on the forum with specific info about what you did, e.g. type and cut of meat, the weight, type and amount of wood, temp you set the cooker at, time in the cooker, internal temp of the meat when you pulled it, types of rubs, sauces, brines, mops, etc., etc.
Also, by keeping notes, if your cook turns out good, you can repeat it.
Keep working on it and be patient with yourself because it will come together.