Since you are camping 1 to 2 hours away, I would suggest two vehicles.
Rest of the family in the other vehicle with as much stuff as is safe for driving in it.
You tow with your van and haul as little as possible.
Pack with weight in mind. Take light camping stools instead of heavy zero gravity chairs. A deck of cards weighs a lot less than a horseshoe set. Razor type 200 mm wheel scooters instead of bicycles take up less space and weigh 10lbs instead of 30 lbs.
I have similar style trailer and a vehicle with more towing capacity, and I still pack the TT as lightly as I can.