If you are a wine drinker look at the Madison / Thompson KOA out East. It's a nice camp and you'd be near about 25 wineries (within about 20 mile radius) and about 40 minutes to downtown Cleveland.
I grew up in Madison which is right on Lake Erie. There are 8 or so covered bridges (if you are into that) in the area. Geneva on the Lake is the next town east of there and in the summer is a destination for tourism (it's gone downhill a bit in the last 20 years but we always seem to visit when in the area). About 1/2 way to Cleveland from there is Headlands Park or Fairport Harbor that have pretty nice beaches. Cleveland also has a bunch of other museums and a great theater district. If you're a gambler there are a couple casino's in the area (one in downtown and another out in the Southern suburbs). The football HOF is in Canton about 1.5 miles down the road.