Shakugan no Shana, Suzumiya Haruhi no Yuuutsu Recommendations
Both have the same character designer, Noizi Ito. There are similar elements in both stories, such as the time-space continuum and the school life scenario.
In The Melancholy of Haruhi Suzumiya and Shakugan no Shana, a normal boy (Yuji and Kyon) is thrown into a completely abnormal world when they meet a girl with special powers (Haruhi and Shana). They both have elements of action, comedy, and romance; with Shana more on the action side and Haruhi Suzumiya more on the comedy side.
Fantasy. Subtle Romance. Comedy. Well build "main group".
Super strong female lead gets in contact with average boy, who is - somehow - special. Although she needs him somehow, she tends to push him around. Seeing Shana wanting to take off her cloth - then remembering Yuji ... just make me remember Haruhi, taking her clothes off in front of the boys ... until Kyon becomes something special.
Further Haruhi and Shana look somehow the same ... and behave somehow the same. (Each has her dark side, too.)
Both of these shows similarly combine the "school life" and "sci-fi" genres in order to create a very interesting overall feel. As an added bonus, character designs for both series were done by the same amazing Ms. Noizi Ito, so you're sure to enjoy the familiar style.
Characters of both Shakugan no Shana and Suzumiya Haruhi no Yuuutsu are designed by Noizi Ito which gives you a feeling of high resemblance between the two series. Aside from the art and design, both heroine projects strong character and personality. Both anime series also deals with super natural events