I gotta rewrite my story for Luna out a little more. I see her as a Magneto-esque figure, who's been kinda neutralized and placed into a figurehead role of "princess" with no real power to speak of. She's cursed with immortality and forced to live a life she doesn't really understand in a world that's totally foreign to her. She's been imprisoned on the moon for 1,000 years, so even years later she struggles with the culture shock of a modern Equestria. The only one she truly loves and cares for is her son Astoria, and her desire to be a good mother and give him a happy, maybe even normal life fuels a lot of her choices in her new post-moon imprisonment life.