Monetizing Article Directory Sites

I own four article directory sites - two on Wordpress platforms and two built on other platforms. These sites need work to upgrade them.

I want to brand them with my own header across the four sites and I wish to monetize them by offering, not only adsense on each article but by offering a section for "featured" articles on the landing pages where customers can place their articles for maximum exposure for 5days, before being automatically replaced. Customers will pay to have their articles featured.

The sites are:

Articlesviewer.com
Articlesisland.com
Articlesici.com
Mydailyarticles.com

Please check out the sites and feel free to discuss your proposals with me. All genuine offers will be considered.

Thank you

Martin