I'm Kinda late to this party, but;
I think many missed the point of the OP question. They asked what do you look for in a campground, not what should I look for in a campground. As Valhalla360 suggests, how long we're staying may make a difference. That being said, even if we're in the travel mode and only staying overnight, I still look for the same things. However, in Travel mode we will settle for a little less.
Reasonably level sites is one thing at the top of our list. I realize that water and snow runoff has to go somewhere, but you don't need a 1 foot drop to accomplish that. Hook ups, E, W, S need to be in decent condition. I hate being packed into an RV park like we are a sardine in a can. Stayed at a few where your slide out was up again you neighbors awning. A place for our dogs to air is another big one. Things like shade, a convenience store and laundry are normally not deal breakers,, but all things being equal, we will stay at those parks over those who do not have them. I am not a fan of the good sam rating system. Don't know who rates them and what kind of rig they run, but many of their 10 rated parks are not for us. Like the rest of us, you will learn by trial and error, what fits your style.
Safe travels
