My two cents:
After fits and starts at the beginning with my water pan, I found good advice in an online forum like this one. Fill the pan with water right after one chimney of lit charcoal is added to one chimney or more of unlit charcoal. Set the bottom vents to two fully closed and one fully open. Then let it run for 20-30 minutes before I put on any large meats (brisket or 2 pork butts). Do some meat prep during this time, injecting or rubs. When the temps get to my target or above, add the meat.
When I didn't following this rough timeline, the temperature would drop because too much volume was added all at the same time that was at room temp or lower. The chamber will eventually climb above 200, but then I have to open all of the bottom vents, then watch for when the chamber temp hits my target, and adjust the vents to stabilize. Watching the thermometer, moving small metal vents...way too much work for me. Much easier to be patient at the beginning of the process.
Clean up is usually easy, as long as I get to the pan soon. After it cools, but before it starts to cake. Usually after dinner is a good time.