I can't say anything to disagree here. That said, she fulfills her role well and I do feel as if ultimately she will be lost regardless of which route the player takes and I'm content with that. She's pitiable, yet despicable at the same time.
As for Titania though, I don't understand the hate. She has a marvelous character. From the first moment where you meet her in the Adventurine woods, through all her interactions with various characters. Regardless of which route you take, there is development. Her personality clashes with many other characters, from Amaria, to Taka, to Florinia even and those interactions enrich both characters, and develop them further.
She also has some of the best lines in-game.