Hey Ryan, for what it's worth, I think your approach makes sense and your reasons for changing some dependencies are sound as well. Good post, thanks for the detail! Oh, and happy 4th.

Is there a way to create a tasklist for the Drupal 6 migration? That way you and your core team can work on the really nasty dependency changing stuff and maybe put out some stuff for the rest of us to work on? Happy to contribute code if needed or port a sub-module.