I'm still more in favor of Django. There is more to learn about it, but almost all Flask projects that get beyond the weekend-project stage end up reimplementing stuff that is in Django, or working around that lack.
The interplay between ORM, migrations, admin, CRUD, API, Forms, etc is just beautiful. Doing that with SQLAlchemy and the like is possible, but may create a bigger mess than starting out with a slightly less lightweight Django. project.
When using Flask, I like the fact that for form handling with an ORM, there's a flask-wtforms plugin, a wtforms-sqlalchemy plugin, and a flask-sqlalchemy plugin. This is part of the reason why I'm sticking with Django.
The interplay between ORM, migrations, admin, CRUD, API, Forms, etc is just beautiful. Doing that with SQLAlchemy and the like is possible, but may create a bigger mess than starting out with a slightly less lightweight Django. project.