To be honest I haven't used South in about a year so I don't really know how it has changed. But with South I always seemed to be running into issues of it allowing you to modify existing elements of your schema but not add new elements or modify types in your schema.
I started using South about two months ago for both my personal website (http://ankursethi.in) and a large-ish CRUD app that I'm working on. In both cases, South has been able to add to and modify the types in my schema. You should give it a whirl again.
