Booking your first stay at a UK holiday park can feel like a lot of small decisions rather than one big one, so it helps to work through them in order rather than all at once.
Where it's worth spending rather than cutting corners is on the things that affect your actual comfort: a caravan or lodge with enough bedrooms that nobody's sharing a room they'd rather not, a park close enough to what you actually want to do that you're not driving an hour each way, and decent waterproofs and footwear so a bit of British weather doesn't spoil a day out. Saving money by squeezing into a smaller unit or picking a park purely on price, regardless of location, tends to show up as a less enjoyable week rather than a genuine saving.
On-site facilities are worth checking properly rather than assuming. Look at what's actually included in your stay versus what costs extra, whether the pool, if there is one, is heated and what hours it runs, and whether there's anywhere on site to eat if you don't fancy cooking every night.
Families with younger children often lean coastal, since a beach gives you a ready-made activity that needs very little planning: buckets, spades and a few hours, and everyone's entertained. Couples or those wanting a slower pace, or a base for cycling and walking rather than swimming, often prefer the countryside or Broads setting, where the pace of the holiday matches the pace of the surroundings.
Pace is worth planning around too. A multi-generational trip works best when the itinerary has some flexibility built in, a gentle morning walk that suits everyone, followed by an afternoon where younger children can do something more energetic while grandparents have a quieter few hours back at the caravan. Trying to keep every generation doing exactly the same thing for a full week tends to wear thin by day three.
For more detail, see
Tingdene Holiday Parks UK.