Bear (I think) gave me advice to leave the tray out to help improve air circulation and keep those pellets burning. So I did. B
In regards to your avatar and signature the 1983 Piece of Mind album/tour was excellent and one of the guitarists Adrian Smith or Dave Murray had a guitar or T-shirt that said, "Iron What?" on the front and this is the acronym for what was on the back IFMTW. It was the only fan club I was in. I was fifteen. Cheers!
I stripped out everything, and stored it away. I use the water pan empty because it helps keep drips off the element and I think it helps spread the heat and smoke.
In my case, yes. Your results may very depending on many factors. A lot depends on your model and vintage of MES. Some folks have a hard time keeping the pellets lit. I leave my drawer pulled out a ways. When I was running brand X pellets, I found I needed to remove it altogether. Just do what works. What does the ash look like after the pellets at burnt up? They should be greyish-white. If they are black, that is a sign of poor oxygen flow.