Honestly most of the characters mentioned in this actually have their fan bases so I wouldn't call them underappreciated. I would argue characters like Edward, Tellah, Gordon, Reina, Relm, Strago, Cait Sith, Amarant, and Penelo would be more of the underappreciated. Largely cause most of them get a lot of unnecessary hate from the fandom or get overlooked for more popular characters when they are pretty badass and often really good characters.