Pulling the chip tray and loader out increases air intake, so you can play with how fast your pellets burn with this. I use the tube in mine, but with that I pull out my chip tray about 2 inches and then play with the chip loader depending on wind speed for the day. There have actually been times when I set up a small fan outside the MES by the chip loader to help with circulation. I haven't done that in a while though.
I just foiled my water pan and stuck it in there empty. It catches drippings, but I think it also help distribute heat a little more evenly. Some guys fill theirs with sand to help with heat retention.
I use an aluminum tray that I cut to size and flip upside down. I think
Bearcarver
does this, too. He's a great resource for all things MES.
Depending on moisture content. It wouldn't hurt to do this every time, but I haven't found the need to. With that being said, I live in a relatively dry place. If you're atmosphere is generally humid, this could become more necessary.
Let us know how it goes!