We've camped some mid=state:
Lake Strom Thurmond - Hamilton Branch State Park - sites right at water's edge, large wooded sites. Nice Army Corp campground at Modoc, though we haven't stayed yet.
Lake Murray - Dreher Island - lake sites
Cheraw State Park - again right on the lake
We tend to like to go where we can have at least a water view, though water front is better....makes it easy to slide the kayaks in the water for a sunset paddle.
In the upstate there are several campgrounds on Lake Hartwell with lake front sites, both Army Corps and State owned.
Ya never know when we might sneak up onya....