Regarding apps, I was just thinking you could create a directory structure like this, essentially eschewing the whole concept of Django "apps":

    <project>
        src/
            <package>/
                models/
                    __init__.py    # Import all model classes (necessary for Django to find them)
                    some_model.py  # Define SomeModel class
                views/
                    __init__.py
                    some_view.py   # Views for SomeModel
                settings.py        # Add "<package>" to INSTALLED_APPS
                urls.py

You still need to register the top level package as an app for Django to find things, but then you don't have to deal with Django's concept of apps beyond that. All your tables will be named <package>_<model> by default, which seems nice.

If it turns out later you need resusable "apps" for some reason, you could always add an apps/ subpackage for them.

I haven't tried this in a real project, so I don't know if there are any downsides, but it seems like a decent approach.