Sounds good to me. Theres too much to do to have big debates or polls about every aspect of the world. Unless anyone objects then I think we should use whatever people bring to the party. Maybe a guiding principle should be that you actually have to submit a substitute of equal strength before you can seriously object to stuff. Picking between two detailed and worthy things would seem better than thinking about whether to dismiss a single option. You could have local calendars and season names anyway, its only whether there are two moons or something of equally global scale that a consensus need be reached.

In the DragonLance series there were three moons of which most people did not know about the third dark one - Nuitari I believe it was called. It's not entirely unreasonable to go with one and later have a second anyway ?

Of our solar system we have a number of easily visible planets of which I have never seen Mercury even though its very bright and we don't even have magic to factor in.