I've been working my way through the recommendations in the original post and the link.
Last week I added 5 firebricks to the oven. I still get pretty wild temperature swings at the smoke and lower temperature settings. However, at say 325 and above, the swings are much smaller, and at the highest two settings, the temperature is pretty stable.
So far, I'm having the best luck with temperatures of 350 to 450 (High) and cooking burgers and steaks that do well under high heat. Long and slow, like for pork butt, I'm no sold yet.
I do really like the convenience of the pellets and really like the overall concept. I've just got to keep playing until I figure out the low temperature thing.
Has anyone tried to close up or open up the chimney? Mine is set fairly open and I thought that might be allowing too hot of a burn.
I was getting lid drips on long cooks, and that was a mess. I bought an oil drip pan that's about 1/2" deep and 2.5' x 3', and that works great. I just pull the Traeger up on it and the drips are easy to clean. I might also try one of those big floor mats that Costco sells as that could be rolled up.
Lastly, I did Mac and Cheese in the Traeger. I made boxed Mac and Cheese, and then added some grated Cheddar and some grated Smoked Jimmy Dean Sage Sausage (Smoked it on the Traeger), and a few home grown Jalepenos. Put it all in a cast iron fry pan and put that on the Traeger. It went on for 45 minutes on Smoke and then 350 for about 45 minutes, Oak pellets. It tasted really good. Next time I will try it with home made Mac as the box stuff was a bit dry (suppose I could have added milk or butter).