We did some looking around in some of the areas you're looking at a couple of years ago before settling on the Crystal River area further north.
Sebring was a nice area, but the one private CG we stayed at we didn't care to stay long term. Instead we stayed at Highland Hammocks SP a few times. There were some nice golf courses and plenty of lakes around there.
Arcadia offered a few potential parks. We stayed at Cross Creek RV Park for a few days. It's a clean and well organized park. Lots of activities. It's well out of town though.
http://www.crosscreekrv.com/In fact, there are a couple of parks in that area north of Arcadia you might want to check out.
Another one with an Arcadia address, although it's really closer to Port Charlotte than it is to Arcadia, is Riverside RV Park. This was a very nice place, but more expensive than further inland. We have some friends that stay there and have heard it's getting difficult to get reservations for any length of time.
http://rvonthego.com/florida/riverside-rv-resort/Here's a link to RV Park Reviews.com for the Arcadia area. As I mentioned, there are some parks worth checking into in the area.
http://www.rvparkreviews.com/regions/florida/arcadiaGood luck in your search. It's a good thing you're looking into snow birding areas early. I suspect it will only get more difficult to get into a park as us boomers retire. We did a 6-7 week trip in '13 to find a park(s) we might like. Went from north down to the keys. Finally stayed for a month at one park (Rock Crusher in Crystal River) and now stay for 4 months.
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