I agree, on ns7 it could be implemented as a core feature.
I think that notifications could be enabled by default. On a new installation I'd expect notifications are delivered to the local root account. Further config steps needed
- set an external address under root's profile
- configure smart host (optional)
Software updates should be disabled, as specified by the upstream default. The admin is the only responsible of applying updates to his system, and can decide to enable automatic updates.
About ns6: I wouldn't implement new features on the 6 branch. Only bug fixes. However, after implementing this on ns7 we can see if a feature backporting is possible.