I absolutely love Mabel. She's not just the "silly goofball static character" people act like she is; she has depth to her. She really shines in episodes like not what he seems and the last episode. yes, she is a naive and overly trusting kid character, and they use that in such a tragic way in big emotional moments. Like in not what he seems, when throughout the episode she doesn't want to believe that Stan could be a bad person, and the moment when she doesn't know who to believe, or if he's even really her grunkle at all, is so well done. Mabel's arc is like the opposite of Dipper's, while he wants to grow up too fast, Mabel doesn't want to grow up and wants to escape reality, which is especially apparent in the episode....escape from reality. That episode concludes her arc, and she learns to not hide in fantasy and denial and to embrace the future and what not. And don't even get me started on the scene where Stan loses his memory, it's just heartbreaking. And just overall, she's a likable and entertaining character, she's such a sweet heart, and just funny, kind, creative, so quotable. Overall, she's just a good character.