Quend Plage is nice with a good dog walk. Wissant is perfect for the tunnel too but it's busy. We use Pont De L'Arche too. All good aires. Neufchatel en Bray has a private aire, its flat but a bit pricey at E13, although you get EHU, water etc - the pay machine never works there so you will need to get the bloke from the campsite next door to open the barrier.
+1 for Neufchatel and you are right about the pay machine lol
I am going into space in a vehicle made from over 3 million components, each manufactured by the lowst bidder - Neil Armstrong