I don’t know about Stalin’s Park, but the Szoborpark in Budapest wasn’t anything like a celebratory place; it was more along the lines of a museum than anything else; they have all the old statues on one side, and on the other, they have a replica of Stalin’s boots, which were all that was left in 1956 after they toppled the statue of Stalin during the revolution. And there was a little building where they were showing some rather surreal Hungarian films from the Communist period where they encouraged people to rat their neighbors out, and other stuff like that.
I kind of imagine that if done right, a statue park of Confederates could be interesting for much the same reasons.