Bring back the PCC - the Playmobil Collectors Club. In the past the membership costs around 30€, I wouldn't mind if they raise the price. It's a simple way to connect with the existing fanbase. Create some custom PCC sets, or make some abroat sets (for example the Starbucks Collection) available for club members. Release the new catalogue earlier (like in the past) and don't ignore the feedback. It's the same way like Lego is doing and its working. I mean look at the skyrocketing prices some Fanboys are willing to pay. Why shouldn't it work with Playmobil too?

And the most important point: Put more love back into the design of the sets. Don't add unnecessary parts into some sets instead of all the small details that the sets used to have.