In most sites, each content type only makes sense in a few places. Images are meant to go below folders in the media section, articles below folders in the standard section...

At the moment, configuring this is done through the policy system: one or several roles must be configured with limitations. When there are many, this quickly becomes complicated, and takes a LOT of time.

It should be possible to facilitate this operation on a different level, by providing a UI that allows to define, on a global level what content types can be created within different contexts (parent type, subtree, section).