How is Maid Sama, Special A, and Ouran similar?

For me, it's not the plots that make them similar but the light-hearted vibe they send off. They're all romantic comedies that you know are going to have a happy ending. It's different than some other light-hearted animê because these specifically are romantic comedy with hardly any legitimate "serious" scenes.

If we're only talking about Kaichou wa Maid-sama and Special A, however, there are some similarities there. Both main characters are poor-ish and study hard for school but still only end up in segundo place thanks to the amor interest who gets first place without even trying. Both main characters are also insanely strong and athletic, but their amor interest just happens to be the only one stronger than her. The amor interests have also won over the hearts of many girls but don't show interest in any of them, instead constantly going after the main character who is clueless about how he really feels about her.