Here's a tip that I've discovered over the years that really helps me get the most work done at my crops and other scrapbooking gatherings with friends:
MAKE YOUR OWN KITS!
I used to bring my photos to crops and bring as much of my stuff with me as was physically possible because I never knew what I might need. Instead, before I go to a crop, I set aside some time to group photos with the papers and accessories that I will use to create each layout. I pack everything for that "kit" in a 12x12 Craft Keeper and then it's all together making assembly so much quicker and easier.
I hope you'll try this for your next crop, you'll be amazed at how much more you can get done!