Oh! Well the more I thought on it, the more I liked the idea of Luna as Loki, especially given the Nightmare Moon arc. Loki and Luna are the younger siblings who feel overlooked, though they do have very different approaches to this.



I also tend to associate Thor himself with the sun, as he's a very strong and warm individual who, like Celestia tends to take the world on his shoulders (after he learns what it is to be worthy of Mjölnir. ). He's the older sibling who looks out for Loki, even when it means he has to do things he doesn't want to do (And Celestia does this too, she had to banish Luna to the moon for 1000 years but to me it's very clear it hurt her very much to do so.)



But largely I would say it is the sibling dynamic!