La Bouysse is in a lovely quiet situation, away from the crowds, and I doubt you'll find anywhere quite as well situated in the Ardeche area as it's a much narrower valley and sites are more hemmed in between the roads, and the river. We've stayed on lots of sites in the Ardeche over many years, and loved them all really! L'Ardechois is the best, in my opinion, near Vallon, but it is expensive. The two sites adjacent, Le Mondial and Le Provencal are just as well situated, but less expensive. Camping International, across the river is a nice site, less shady than Le Bouysse, but all these sites have river access. Up the river a bit we liked Camping Bastide en Ardeche at Sampzon - an ACSI card site - then there's Le Riviera Camping and Soleil Vivarais and Aloha Plage - again all have direct access to the river - we've not stayed on any of these three.
At Ruoms there is Le Coudoulets, which has a nice pool and slides, and again access to the river! Again this is an ACSI site, as is Les Arches further up river again, and Le Ventadour - which we've had a look around, but not stayed at. Too many to choose from, really, and over the years we haven't found a site there that we didn't like.
If you can go more towards the last two weeks in August you could stay on an ACSI site, and combine some days at 'normal' tariffs, with some days at the ACSI tariff, and perhaps save some money overall - as Ardeche sites tend to be on the pricey side, overall.