Since it looks like all the lore that’s ever going to be fleshed out has been explored, what do we wish they had done that they didn’t? For me, it’s Nightmare Moon. Why Luna became Nightmare Moon is only touched on once or twice in the show, and always in vague terms about jealousy or feeling unappreciated. I approve of ambiguous storytelling, but as is we really do not know enough about what exactly influenced Luna and what role Celestia had in her ultimate turn to evil. It’s a fascinating piece of lore I wish they had delved into in an episode, mainly because it’s such an important part of Luna’s character development.