The northern islands and coastline, like kirk, hvar, Crikvenica, farther away from Dubrovnik, are generally less popular. Though, they are generally not very touristy anyway. The island of Vis was a militarized island and may now be open to the public - completely uninhabited. There are literally hundreds of little islands. My god-family lives there and it is generally okay to be topless or nude in secluded areas/beaches/etc, even in popular beach areas. In the summertime, you can't escape it. The local hospitality is incredible, but the port cities on the islands tend to be full of foreigners (British, Italians and Germans). We always pulled into port and then hiked off to other parts of the islands.

Korcula is a must if you want to camp and hike. There is a beautiful lake in the middle of the island and tons of hiking and camping areas.

Hope that helps! If you have any questions just email me, I can always ask my friends out there.

i've been there 2 years ago, but we only had a week so i can't give you any helpful location ideas.

in our experience, and we've also heard that from other people:

where ever you go, go to the nude campgrounds, because those are generally less popular
and way more beautiful...
i know that croatia is the "new" country to go to for may europeans, and it's very touristic anyway.

i've been told the further south you go, the less touristic it is.

good luck with your journey...