Wow! You are SO helpful and smart! Do you want to collaborate on a project?
If you went to my site you saw the images on the home page which is what I am referring to as a "slider". As you know, with any basic theme you can have this appear on just the home page or on all pages. The concept with the City Portal was to have my own section images on the home page, like Real Estate, Business Directory, etc. When you then clicked, for example, on Real Estate, you saw another slider, but this one was unique to the Real Estate section. The idea was to sell these slider links which would then take you either to their own site, or to a mini-site on our site. These section pages would also have unique ads in a unique sidebar, again relative to the section.
I might mention here that until the project collapsed, partly because I left Panama, and also because the developer never followed through with the unique sliders, there was a huge amount of interest from advertisers. I had approached some of the banks, grocery stores, hotels and so on and they couldn't sign up fast enough, partly because I said there were only five slider positions available in each section.
On the unique slider concept, although I am no coder, I suggested a simple "if/then" statement, "if page-ID=XX then slider Y". The same would be true for the unique sidebars. Maybe too simple?
To me City Portals are an excellent opportunity to build out very user friendly sites. No one uses the old Yellow Page directories anymore, but allowing them to navigate exactly where they want to go, then providing useful information is attractive to both users and advertisers. Who pays any attention to Google or Facebook ads, regardless if they match your search interests? They are "push" not "pull" without permission, so they are just more garbage.
Just one man's opinion, of course.