[Django]-How to decide how to split up your Django project into apps

If having one model per file would be the perfect answer for you, there’s an app for that.

I’ve never done it on a scale of 80 model files but I can certainly point you towards another stack question:
About 20 models in 1 django app

http://djangosnippets.org/snippets/1838/

What kind of circular reference problems are you having by the way? If it’s with ForeignKey definitions, here’s a way around that…
http://docs.djangoproject.com/en/dev/ref/models/fields/#django.db.models.ForeignKey

You can also look into django.db.loading.get_model, but some may frown on this.