Hope I'm not too late for the party.
Reheating larger pieces whole will take longer than you think. If it takes 15 hours to cook and bring up to 190*, it may take 4 hrs to reheat to 165* for serving (minimum recommended reheat temp for leftovers). It doesn't take as long to reheat because of lower target internal temp, and, a lot less internal moisture to evaporate from the meat as part of the cooking process. Reheating can dry out the meat, as I'm sure you already know...preventing that is the trick.
As to finished temp in the smoker, take to a probe-tender state, whether that is 180*, 190*, or higher...you don't want to reheat to that high of temp or it will dry out...possibly quite badly. Rest after smoking and allow to slowly cool as you normally would to redistribute the juices. Once the I/T drops to around 140* it should to be chilled more quickly, so fridge, or a hit in the freezer for an hour would zap some heat out of it...then to the fridge.
Did you consider slicing prior to reheating, or are you intending to slice after reheating? Reheat for sliced would be faster and you could put the slices into a covered pan with broth.
As for pulled pork, pull it after resting and reheat in it's own juices...toss it in some of Chef Jimmy J's finishing sauce to step it up a bit.
For the brisket or pork shoulder, if your oven allows for the load, you could smoke them to 145* or so for flavor, rest, cool, chill, then reheat to finished temps the next day. It would require some planning on your part for timing to finish cooking in the "O".
Eric
