Michael,
The categorization of the CR should be sufficient for any application. What needs to be done is make sure all packages use the CR categories instead of their own system. This way categories will be consistent across the system and it will be easy to query for everything in one category no matter what package it belongs to.
I am specifcally talking about an interface to manage the addition of keywords to the master list of available keywords.
A rating system would be a great add-on package. It could probably be implemented similarly to general-comments.
You are correct that these features need to be site-wide and not specific to whatever content management package is installed.
