We will be going as a family of 5 this summer (three DCs one almost 14, and two preteens). All are confident and capable swimmers, so preferably ones with good outdoor pools and maybe with a water slide or two.
We don't have a tent or caravan, so will be using the campsites own accommodation.
Would also appreciate views on ones to avoid like the plague, and any handy hints of how to make the holiday as good as possible. Not asking for much, then! 
Thanks very much if anyone replies.