Glamour Gleam is a character and the same as Bonna Fide. Rose Quartz is a character for now; we could add (character) or (crystal pony) to the tag. Gallic is a character. Agate, Agatha and Amethyst Maresbury are all one and the same pony. The latter could be made the main tag with Agate and Agatha as aliases. Cinnabar and Quicksilver are the same pony. The tag Mercury should be removed from her because that’s an entirely different pony. (I think I should look out for those pictures of her that are only tagged Mercury.)
Also, Adorable Waves could imply Amber Waves.