Jo-anne
Surely your own campsite book can answer this for you!
As a good all round package with good facilities Polmanter, Halsetown St Ives takes some beating.
There are also some good CC sites worth using but not with the luxury you probably enjoy at Hillhead.
Where I have just been is , for us the best all round , location , price etc. I'm not prepared to divulge this little gem on here!!
Beach wise, a lot in the summer ban dogs.
One of our favourite beaches is Caerhayes beach by the Castle of the same name. Has a small cafe , toilets and is a real sun trap. Dogs allowed.
Carnon Downs was also very good at Christmas but you have been there.
I noticed a really pretty wild camping place between Mullion and The Lizard but it had no facilities other than a water tap.