Excuse me but Rapunzel does know to take bad guys seriously despite her sunny nature and knows how bad they are which is why she never tries to get through to them despite pasts like Lady Caine, Baron, Gothel, Zhan Tiri, you named it. I hope you understand that.
And he/she also proposed a character that has a page on the villains wiki which is Varian and he has turned to the dark side in the first season and did some villainous acts before redeeming himself in the last season. Even though I don't watch Tangled: The Series and Varian does seem like a friendly person despite having corrupting qualities but, he is FAR from Pure Good.
Plus, there is only one character in Tangled who is Pure Good and that's Rapunzel.