We've camped at Roper Lake several times. Very nice park. Not sure where Windyhill is. Haven't gone anywhere North East AZ, other that River Island Park in Parker. Not sure about the Vegas area. Hosting Thanksgiving at the stationary home this year, so couldn't manage that. Perhaps another time.
Windy Hill is a US Forest Service campground right on Roosevelt Lake. It's about 3 miles or so East of the dam on SR 188. Nice campground with bathrooms and showers, but it is dry camping. No power, water or sewer hookups available.
Oh, yeah - it's hot in the summer too, but they allow you to run your generator all night several of the campgounds.