I think it's pretty simple. The B2P model for TSW means that FC need to market the game to make money through new box sales or item shop purchases. The sub model for AoC means that AoC provides a steady - though declining - revenue stream which doesn't require marketing effort. In other words, I am pretty sure that Sezmra and Tomium do not have unlimited discretion as to how much time they spend on TSW and how much on AoC...
Of course, this is a very short-term business model, which doesn't take account of the fact that AoC most likely has more potential than TSW in the mid to long term. But given their financial situation, FC's decisions regarding their live games have been driven by short-term considerations for quite some time (ever since TSW was taken B2P).
Couldn't agree more on the awesome work done by players like Moriala, Cynara, Johara, Slith and Henryx though. So much stuff which FC could use for marketing the game, if only they made an effort. And you are absolutely right about Waldgeist...