Worst and best manga mary sues ever?

If you have seen the Fruits Basket anime, I understand that you'd think Tohru to be a happy-sue, but the manga explores the reasons behind her nature. How she forced herself to be so cheerful, how she really felt about her father and how she thought he would take her mother away. How she continuously scolds herself for loving Kyo for fear of losing her mother's memory. She is actually a very complex character. The anime ruined that. But this topic is manga mary-sues. Tohru is NOT a manga mary-sue, though her anime counterpart may be.