Surely someone has some ideas? Some that I have considered are:
Make an electronic map with campsites highlited on it.
Allow people to upload their own photos of campsites.
Add a last updated date to all campsites details.
Your site is pretty good as it stands Andy. We've used it a lot this year while planning trips.
Your own three suggestions are excellent and would make a great site even better.
How adding about the facility to do a search by site name or partial name? It would speed up searching when looking for a site one has looked up in the past.
Modify the "Star" grading system to cover location, facilities, staff/owners' helpfulness? As it stands it is rather a blunt instrument - I've found it difficult to rate sites at times - 'super location and nice owners but iffy loos !!'
There is already on the web a freely available file for "AutoRoute" that includes all the UK sites of the two main clubs (CC and C&CC) and their "Certified Site/Locations). If you (or someone) could add the contents of your site to that file it would be a superb resource. A good number of the camp sites you have listed are already included in the "AutoRoute" file.
Sorry - Long reply, but you did ask!
Keep up the good work and thanks for a great site.
Dave W