Like others, we like the packed and ready approach so you just add fresh food and clothes and drive off. We mainly do weekends away so may have to review this for a longer trip, but it would just be food and clothes that we'd look at.
Kitchen: something to eat with, off, drink out of, cook in (ss pots x 3 & CO), season cooked food, comprehensive herb container, the odd tin of something if we are feeling lazy, dish drainer (contains all associated with), sullage bucket, 2 x bendy chopping boards, the usual utensils for smashing / whipping / chopping / skin removal ... you get the idea, a ss bowl (cake mixes, etc), paper towel, pegs, mozzie coils, first aid kit, extinguisher, glad wrap, alum foil, baking paper, led light strip.
Shower: pop up ensuite (bag also contains 2 x blow up li-lows), bucket, cup, wet pack (1 each his / hers), loo rolls.
Anything that came with the camper (of course) like pegs, poles, ropes / gas bottle / 2 jerry can bins / bedding / clothes bags (his / hers) / pillows / table / chairs.
We also have a camping box for the ute which contains: 2 x solar panels and lead, timber in box, emergency gear (tow ropes / snatch strap etc) / extra canvas for camper / axe / spare loo rolls and paper towel / dunny / dog beds, food, bowls, leads, toys / raincoats / ozpig.
Probably a few other things but I can't think of them now, so I guess they aren't important.
Kit_e
Edit: Those few other things I couldn't remember are: Levellers / new alum step / extra long legs - if you own an AS you'll want these at some stage for the hard floor / shower mat / ... to be continued.