How to design a (truly) modular application with CI?

[eluser]liri[/eluser]
To be more clear, the architecture resembles a type of group and it's children, such as:
Management
---> Users
---> Profiles
Reports
---> Report 1
---> Report 2

So that the actual functionalities are the sub-categories (children) and the categories (groups) like Management
are just a way to group the functionalities into some organization logic.
With that said though, I would like the sub-categories to be modular so that when Management link is clicked it
"scans" and lists all the sub-categories related to it. So the sub-categories become modular, can be added and
removed.


After looking around a bit, probably the Modular Separation library is what I need, which will result in having the
Sub-Categories (the actual functionality pages) being controllers, and these can be added/removed.

If that is the case, what would Categories be? the modules themselves?