Deffo has been updated to Mobilizon 1.0.6, and a couple of federated event sources have been added. We seem to have the only Australian instance, and most of the imported events are French, so there's not a lot of relevant crossover. It's good to have some stuff coming in to show what things look like though.
I'm not sure there's any timetable for Mobilizon customisation to improve, but I'm holding off on any kind of publicity or anything until I can reliably make the site look a little different and at least have the correct name on it.
It should be stable and safe to use though, if anyone discovers and needs it.