In the app window I would add a checked box named "show libraries and dev" that it should be unchecked by default. Infact I don't see the need for the user to see extensions like libxx, gtk+-2, glib1...
If u look at ubuntu, in the first menu there is a program called "add - remove programs" that is a list of choosed programs that is more user friendly then the one in synaptic.
So I would reorganize the extensions where each extension can be one of this 2 types:
-main program
-dependence, library, development
If the user will check the box they'll be showed