1. vBulletin (and other forum software) integration for the comments system.
2. Easy, and totally flexible templating system
3. Pagination (ability to efficiently divide long articles/texts into differnet pages).
4. Timed publishing (as in, the ability to automatically publish an article or text/content sometime in the future yet; ANTE-dating)
All the rest are standard stuff for any CMS, but the above seem to be lacking always.
Good luck.
Nicholas
P.S. A few years back I wrote an article-processing system in Perl (it hasn't been updated and is very obsolete now, of course), but the features may interest you:
You can read the features
here. Good luck!