Modularity

A related factor to accessibility is modularity, or the ability to implement new aspects to the application without having to rewrite the existing parts.

this suggests a central log that added modules can interrogate to see whether the entries are relevant to them. The added modules should make themselves aware to the rest of the application so that they can be accessed via menu options and proper authorisation can occur.

I think this needs to be addressed further so comments here are especially welcome.