Congrats on the upgrade!
I agree, a lot of stuff does accumulate. The only thing we pack for a trip is basically food, towels, clothes, laptop, camera. Most everything else is in the RV already, like toothbrushes, shampoo, pots/pans, toaster, tv, plates, heater, fan, coffee maker. Anything you can find a duplicate of, keep it in the RV.
I keep a packing list that I print out each week to remind me of what should be in there, and what I need to bring.
While you are camping, write down things as you think of them, and bring them next time.