I live in Michigan, and have camped for a total of 5 weeks every season at Muskallonge State Park.
I would suggest a person go to the specific campground site in order to find out what is really available.
The above summary is somewhat confusing for the above particular park that I know well. They do have electricity at each site. And there have always been two separate shower facilities with four or five showers each, plus very well maintained restrooms. Vault toilets are mainly for when there is a power failure, plus there is one by the boat launch.
They were not crowded at all when I was there in June. Even after the Michigan public schools were out for the summer, it was kind of slow. I blame it on forecast summer gas prices of $5 per gallon, which never happened..
Oddly enough, when I went to make my reservation for September, this very morning, many sites were taken. I attribute that to fall color fans and their annual festival type program (arts, crafts, agates, jewelry, etc.)at this park, and the fact that gas prices are now forecast to be more like $3.50 per gallon.
I don't know when it will be rolled out, but I believe the state of Michigan is taking pictures of each and every campsite so you can view every actual site online. At least that is what they told me when they asked me to move my truck so they could photograph my site. Funny though, they did not seem to mind my tent and boat trailer being there.