A water pan is going to eat more fuel I wouldn't use it. I think your seeing more white steam then smoke if using a water pan. What type of lump are you using oak, mesquite, the brand maybe? You need to just cook more briskets brotha, it's going to take at least 50 briskets to start getting it down, don't get discouraged just keep smoking and go on feel use temp if your going to as a reference. You'll eventually get the feel of thing's and start to show consistency, better days to come.
@ JS-TX lol ya