Ive just come back last weekend although a different site.
Definitely make full use of the pool as early as you can on the first day and the last day after you have checked out. Its easy enough to spend all day in there :-D
Food is expensive to buy at the market. A bottle of Blossom Hill wine that you may get in Tesco's for around £5.99 will set you back in excess of £15.00 at the CP market. A packet of pasta (which I forgot to pack) set me back £2.99 at CP but my local store would have only been £1.50 
Crazy golf was still expensive for a family of 4 (£29) and you lose the ball on the last hole (either don't pot it down the last hole or buy some in sports direct and take with you to get a longer game). It took my 7 and 10 year old just 15 minutes to complete the course.
Bike hire (adult) was £19 for 24 hours. It worked out less per day if you had it all weekend. Everyone uses bikes (including staff). They are really handy to take with you and all villa's have bike racks outside to chain your bikes to. There are bike parks throughout. Don't underestimate how far away you may be in your villa from the main plaza/sports centre. We were a good 40 minutes walk this time (Longleat) but our last visit was around 30 minutes walk which easily extended to an hour with a tired child being carried.
Climbing set me back £45 for 2 children, it did last an hour but that hour included completing the forms and getting their gear on.
A torch will be very handy. The pathways are lit but its low level lighting and depending where your villa is situated it can be fairly dark walking through the forests in the evenings.
I didn't book any eateries in advance and we found if we went for dinner around 5pm there was plenty of space available. If you want to eat from 6pm onwards it was more difficult to find a space so definitely book a table if you prefer to eat late.
Bowling was very popular but I found using the onsite booking points often said an activity was full but if you just popped down they often had spaces that just weren't on the system. That was around £40 for 45 minutes.
Enjoy your trip 