Yeah, this should be moved to general or maybe even deleted.
If you want to discuss this its an open discussion in multiple other threads
It is an interesting topic so I don't mind this thread remaining open.
The game is a few years old so its unlikely that InnoGames will maintain the same amount of advertising as it did when TW was a new game. Now with games such as Grepolis and The West, InnoGames have other priorities, as they want their newer games to have a good level of success. This means less money set aside for advertising TW and more into Grepolis and other games etc.
Also, new worlds are made at such a quick rate that some players have developed a start-up culture where they only stay for 2-3 months on a world (Start-up) before jumping to a new world. If there was a longer gap between worlds then maybe those players would stick around, along with creating a larger pool of players in a single world.