I'm curious about why you use Django together with SQLAlchemy, instead of using the built-in ORM? Or is it just separate projects?
I'm not sure it's the most elegant solution, but it has been pretty functional
Fun fact (and a bit of a brag, apologies), I was the contributor that added the “new” Expressions API with the intent of building a reporting platform on top of it. That platform never eventuated but I’ve still got lots of use out of those APIs.