We have also stayed at the Apostle Islands Area Campground, and would rate it "OK". We were put off by a lot negative signage--you know, "don't do this", "don't do that", "STOP--THIS MEANS YOU", etc.
If you are willing to camp a few miles down the road in Washburn, WI, there are two city campgrounds that are real gems. Washburn, Wisconsin - On The Shore Of Lake Superior
Both Memorial Park and Thompson's West End Park are right on
Lake Superior; Thompson's has both a swimming beach and a boat ramp.
Unless you want the beach or boat ramp, we think Memorial Park is the place to go for smaller rigs. It's heavily wooded and very pretty, and usually less crowded. But it is a little tight for bigger rigs.
Thompson's West End Park has huge sites with big-rig accessible spaces, but not as much shade.
And we have yet to meet a City of Washburn employee who wasn't outstandingly friendly and helpful.