I think what constitutes a good site for one person might not work for another. As an example, we love Glanlynn at Bala and have been using it for 30 years (break of circa 15 years between when we used to go there and re-finding about 5 years ago), primarily because of the sailing and fact it's good for group meets (hence recommending for the T6F meet last year) but, in terms of facilities, it is OK but falls well below other sites we use.
If not away as part of a group then we always try to find sites with somewhere nearby that the dogs can have a good run and, preferably, with a nice, dog friendly pub within a mile walk. Aside from Bala, the ones we have visited more than once since having the camper van are:-
Rural Relaxing at Medbourne - this is our bolt hole site where we have been about 7 times for 1 or 2 night stays - small site basic facilities but well kept. Main reason for repeat visits it that it is only about an hour away from home and great for, out of season, Friday afternoon getaways after school.
Waterside House Ullswater - working farm with direct access to lake. About a mile from Pooley Bridge along lakeside path. Stayed there 3 times over last 18 months, and will always be special as the first place we took the van. Facilities OK but it's the location that wins with this one.
Gillside Ullswater - opposite end of the lake to above, well situated for walking around Patterdale, Hellvelyn, etc.. but no good for sailing as about 1/2 mile above lake. We stayed here when Jo was doing a swim in the lake last June, have been back and will go again. Pretty basic facilities but a relatively cheap and accommodating place to stay.
Upper Hurst Farm, Hulme End, Peak District - a relatively small site with excellent facilities but also quite expensive. Used it twice with the van and will be going back this year.
As well as above we have used a few Camping and Caravan Club sites and Haven sites since having the van - not revisited any yet but not saying we wont - all provide a very good standard of facilities and, especially out of season, at some very good prices.
