One of the first indicators that Hayate is actually a nice guy:
Hayate: Himeno, the flowers say thank you.
All of Himeno's flashbacks that involve her mom are heartwarming.
Mikage, the maid at the Awayuki Residence and Princess of Disaster, gives a really good pep talk to Himeno in the anime.
Mikage: If you don’t know the reason, then finding out is the first step to finding an answer. If you’re just worrying yourself without knowing what it is, then you won’t get anywhere. Things are usually just that simple.
Also in the anime, Himeno's whole family tries to free Mawata from her encasement in the tree of Fenrir. And they do it in a Bad AssDeterminator way.
When Hayate kissed Himeno at the end, he brought her back to life at the end of the anime.
In episode 8, after Himeno loses her power and runs away from home out of her feelings of uselessness and confusion, she eventually encounters Hayate - who has been frantically looking for her. When she breaks down crying and tells him to just find another Pretear, he embraces her, telling her it's okay if she wants to quit, and that even if she can't transform into the Pretear any more, she's still herself and there's no replacement for her.
Himeno deciding to humor Mayune and purposefully getting caught in a trap.
The younger Leafe Knights looking up to Himeno and calling her Onee-chan/Big Sis almost immediately is rather sweet and touching.
Himeno redeeming Takako with kindness and understanding in the finale.