No, I am not advocating that we sent dwarf-based satellites into space...yet.
What I am suggesting is simple: add in a possibility that a given world will have more than one moon. I suppose the title could have been more clear.
There could either be a random chance that a given world will have multiple moons, or simply a worldgen option or something like that. Worlds with different quantities of moons could act differently in terms of tides and such if tides and such ever end up in the game.
What is already going into the game could be affected by this too, though. Individual moons could affect certain variants of were-creature. Although I imagine in most cases a were-creature would only be affected by one of the moons, it could be... different, having a dwarf that turned into a rampaging monster twice a month, or worse, turned into two different monsters each once a month.
I guess they'd probably have to be able to be differentiated somehow, though. No idea on how this would work without adding a 'local cosmos' tab or something to legends mode. Maybe the moons could be colorful... although I could see people trying to destroy one of their worlds moons if it turned out Microcline cyan.
Plus, it's a small step towards more space-related stuff. Which, as I remember correctly, exists in some form or another in the grand scheme of things.