Shakugan no Shana's story is interesting but not super unique.
Action side: Basically you have a kick ass fighting girl (Shana) who's lacking in the emotional department meets an ordinary, naive boy (Yuji) who's thrust into a world of magic and monsters.
Romance side: There's a lot of high school drama and a love triangle that spans all three series.
I rated this an 8 because of the action. I thought some of the fight sequences were pretty cool and honestly, I don't need a revolutionary plot to be entertained. The format isn't really monster of the week (which I like) and most of the fights deal with bad guys that last 2-3 episodes and connect to an overarching evil organization. This gives some subtle continuity between episodes which I think is helpful in the context of a romantic anime. If I have a complaint with this anime it's that the romance is frustratingly paced and the love triangle is pretty silly. I'll discuss it more in the characters section but I think they should have done away with the 3rd wheel altogether and just extended Shana's coldness toward yuji. The way the love triangle is set up it just makes Yuji look silly, the 3rd wheel feel like a hollow plot device and the whole story feel a little fluffy.
Art 9: I really liked the animation. The characters are drawn very well and the explosions/energy effects are amazing. Most fights take place inside a "Seal" which is essentially a red-colored stasis field. I think it gives the fight sequences an eerie feel.
Sound 8: Fine
Characters: Shana kicks ass. She's the center piece of the anime and holds everything together. If it was just her I would give the character section a 10/10 but unfortunately other characters drag it down. My complaint come down to the author's choice of setting up a love triangle for suspense rather than going with pure tsundere. The series focuses so much on Shana that making her compete with another girl who has virtually no back story (Yoshida) is just silly. It makes Yuji look like a dumbass too. The net effect slows the character development down considerably, as Shana/Yuji's near death adventures get swept under the rug when morning classes start and Yuji becomes captivated by Yoshida's sandwiches. I like some of the other side characters they introduce but I feel like they aren't developed enough.
Enjoyment/Overal; 7: I think it's critical to go into an anime with the right expectations. If you are looking for a dark, twisted anime to keep you in suspense and rip your heart out at the end then this may not be the right anime for you. Likewise if you want something that's super action packed or super lovey dovey then this may not be a good choice. I liked the finished product because I think the action-romance combo is great, hard to find and really hard to do well. That being said, I think it could have been done a little better in some places.
Violence/Gore: Pretty decent action scenes. Not too much gore but lots of mass destruction.
Romance/Love: slow and frustrating at times. I didn't think this angle was the strongest part of the series
Sex/Nudity: none
