I like this idea, but I want slightly more control. I want to be able to say:
All cities with one or more unhappy citizens switch production to building a temple now.
All cities containing 0 units build a defensive unit.
All cities which produce more than X trade begin building a library when they complete whatever they are building now.
And so on. A heirarchical list of Building Rules, much like e-mail filtering rules, would be very useful.
(And if we could extend it to automated workers, that would be great! I'd pretty much always "Clear all jungle adjacent to cities" and "Build mines on hills inside city boundaries" and a few more things like that.)
Right now, I use the "Load Queue" feature and then modify the list to be relevant for any given city, but then I have to keep track of what's going on, because the city may have grown at a different rate than I expected, or been attacked, or whatever.