With small kids - in our pop up (back in the day), we put a sheet over the material on the pop-up bed mattress & let the kids sleep in their sleeping bags on top of that sheet. Made for much easier arranging. If you have any that are having trouble making it thru the night fully DRY, bring a crib/bed wetness protector to put under that child (beneath the sheet, so it won't wiggle).
We found that using a portable toddler bed guard bar (example -- 16 Terrific Kids Bed Rails Picture Ideas : Souali Kids Room Decoration Ideas
) kept the kids from "rolling" out of the bed & helped keep their "STUFF" contained
. But was short enough to allow a 'doorway' into their end of the pop-up.
I would add a few items:
Drain board that fits in the sink.
Cutting Board (I use the flexible VERY thin ones & leave it on the counter to protect it, even when I'm not using it for cutting on)
Small containers for leftovers
Grilling? Grill tools (fork, flipper, etc)
Griddle (much easier for breakfasts than using pans/skillets on stove)
Cookie sheet/bakeware (SMALL!!) if you're planning on using the oven.
Velcro Strips 6-8"
Extra Bungie cords
Hot Pads & Trivets
Table Cloth for picnic table
Tray - to carry stuff in/out easier.
Enjoy -- know you'll forget something! It happens to all of us!