This is my first review in a while so dont be mean, it is short and sweet :)
Also you can skip to 'Overall' if youre lazy.
I cannot really exactly give an accurate review, as i dropped this series early... ;P
Story: I really think the original plot is actually decent, but they just BUTCHERED IT. There are useless episodes everywere, the plot does not develop at all. They are full of Nagi being a brat. It really reminds me of Zero no Tsukaima, with abuse and stuff :(
Animation: The animation is average for new shoujo anime coming out all the time. It would be considered great, back in the day. Now theres many animes with this style :( Style (imo) is huge-eyes, unrealistic hair, and just pretty people. The animations ok.
Sound: I used to love Rie Kugimiya, now I think her voice is annoying and squeaky. That is Nagi. And the seiyuu for Hayate is Ryoko Shiraishi!! Its a girl but she seiyuued Himeko from sket Dance who I really love!!! The sound is not great, but its ok... other characters are ok...
Characters: I think character development is horrible!!!! Nagi is too tsundere and its a bad tsundere. I love good tsunderes (like Sapphire from Pokemon Special)!!! Nagi is abusive a lot :( While Hayate is too much of a good person :( Waahhh Makes me sad. The other characters... just meh. I dropped series cuz of characters. I couldnt really get to good characters :(
sorry unfinished, WILL FINISH.