So there were a few points in this thread where I couldn't quite fathom why people even bother responding; Maybe it's because I don't buy into the grandstanding, political peacock fights, I'm not sure. Before I even try to touch the meat of the OP content, there's some fundamental things that should be addressed:
1) There's at least one problem presented: retention
2) There's at least one solution presented: cost reduction of cities.
I think we can leave 1 alone, as anyone should be able to understand that it is a truthful issue. That brings us to 2, which hey sure, a lot of people have an issue with. That's fine, except instead of insulting everyone, OP and his lovely mother included, the focus should be switched to "Well that wouldn't work, why not doing X instead?" I'm not a terribly smart or creative individual, but I'm a fairly productive person that can spot room for improvement of the bigger picture. The biggest issues I've seen with retention (personally, as both of these have been reasons that I'm only marginally interested in PnW most of the time) have been the absolute cancerous cyst that most of the community encompasses (no fingers pointed, no alliances spared) and the fact that the type of game is very niche. Most people prefer quick gratification, that's how our society has become over the years. We can't do anything about the genre or scope of the game, but we sure can do something about the community. I think if we start there, we'd probably set foot on the right path to retention.