There's so much content the game engine's starting to give the dev issues. They're working to wrap up existing side girl storylines first and then the game's conclusion/stopping point, which means adding a few more new girls for those. (Tabufa was the last goblin girl type to be added, filling out the Goblin King's harem.) Once those are done extra stuff might be added if the engine doesn't choke on it.
Animations of existing scenes are being gradually added, Victoria got one in the last update and Sequoia in this one. The dev pays someone to help with animations and there's a limit to how much can be spent for that. Renders take a long time to process. And while it might not be a lot for each, adding alternate sex positions and animating non-animated scenes still takes up some of the engine's resources.
I'm all for updating existing images/animations (some of the early stuff is just fugly by current standards), and adding animations for existing non-animated scenes.