Its hard to say what you would need without knowing what you have looked at: big CMS's like
vignette?, little Free Software things like
Nucleus BLOG portal?
How you intend to implement the design and maintenance of the software: are you a one person shop or a multi-person IS dept with graphic designers, programmers, and sysadmins?
Do you have a databse that already contains a large part of your work that the CMS will need to be able to interface with?
For instance, Nucleus is really easy to use. I have not found a writer yet that cannot manage Nucleus, however, the rest of the system is so limiting that it is useless for any environment with more than one writer... its BLOG software after all.
If you are looking specifically for a "CMS" for writers, you might look at
Goose Quill as its interface is specifically tailored to writers and its "frontend" is designed for interaction with the writer's market. It does not have most of the features that you might expect in a "CMS" but it will take very little technical know-how to set up and manage, and ease of use will be very high.
On the other hand, many larger CMS's allow the admin to tailor the backend to limit what a particular user sees. As a matter of fact, many will (should) even allow you to do "front end editing" such that a writer never has to see more than his/her stories in a pasword protected part of the "web site," possibly with comments from the editor, and an interface to upload (cut/paste) new stories.
The latter will of course require more work from an IT department, or from a third party developer to customize your setup.
Ease of use IS paramount... I agree. The best way to evaluate a system is to see how someone else uses it. Only then you can judge actual productivity first hand. You will also see what parts of the system are actually used, and what parts are... really expensive gimmicks.
I am partial to
Free Software as a concept, and I believe that any organization can get a better result from Free Software simply because they do not buy a canned product. They buy a consultant or a developer that will custom tailor a "canned" (but open source) product to the buyer's need. The consultant does not pay a annual API license fee to the software developer, and can in fact see all of the source code. This eliminates a significant cost overhead and "accessibility overhead" for the consultant. Usually the consultant is, like you, a small company, and is therefore much more flexible, innovative, and open to the possibilty of using software other than "their own."
All things considered: a great advantage in most cases.
--gabe