avoid the dump stations after mid morning on holiday weekends. They line will be long and full of rookies that will take forever. I always try to get out of there early on those weekends. Those lines are full of people that don't regularly camp. either they haven't established an efficient routine or they just don't care. I think labor day is the big one. For alot of people they winterize, dump/flush the tanks and take it straight to storage for the winter. For them its now or never. It just seems like those guys wait until the lines good an long to get going. No hustle in their step lol.
I think the best way is when there's a line is to do what you need to do with purpose. while your waiting in line locate your stinky slinky, have your gloves at the ready an necessary compartments open.
When i pack up at the campsite i try to think ahead. think of the next things i need and pack those last. My gloves and tupperware with my elbow extension go right at the front of the storage compartment. Hand sanitizer and/or wipes on the center console of the truck. Pull the black, pull the gray, rinse the hose and hit the road.