Plone is a very capable CMS with extendable user profiles, customized authentication to backend of LDAP or a variety of others.
Archetypes for developing custom content types. In archetypes, you define a simple schema and the system builds the view, edit, search forms for you.
Completely, separate logic and design....meaning separating how your application works from how it functions so that you can change the way it looks without worrying about how it works...
The list of plone features it too long to list here...but you can download and install the app in about 20 minutes and see for your self. Customizing things takes a little more effort in searching for information but there are a large number of support companies also.