Which python project to choose for a database-heavy application
My gut says you want to use SQLAlchemy as the ORM. Turbogears does this out of the box, and probably is the largest player in the "not Django" space.
There was some work on pulling in SQLAlchemy for (or in addition to!) Django's ORM, but I don't know how current that work is (a quick google search found articles from 2008-2009 as the top hits)
I plan to develop a rather database heavy (~100 tables) web application in python. The focus is on providing a nice and task-optimized interface for people that edit or navigate through the data. Other focuses are:

Handle lots of data and complex queries.
Internationalization (translation, timezones, currencies)
Mailings (bulk emailing as well as notifications)
Easy integration into other websites (pull data from or push data to the application)
A role based authentication scheme. (ideally enforcing one role at a time)
It should be easy and fast (for python programmers) to create custom forms and workflows to work with the data.

I've read a lot about django, turbogears, pyramid, webcore, … but I'm still having a hard time to figure out where to start.
My current evaluation would suggest that turbogears is the way to go. Pyramid seems too much to learn about. Django seems to be too publishing focused. WebCore seems a bit to immature to base such a project on it.
Am I overlooking something? Are there other more suitable python frameworks? Is my information about some of them plain wrong? Which framework would you choose for this project, and why?