11eyes, in the beginning, showed potential to be a "10" or "9" grade anime. Some shows went on and grew the beard. This one, on the other hand, devolved into something else. However, this wasn't exactly a devolution into the worst of the worst.
Story - 4/10
The anime showed pretty strong potential to be a very good supernatural themed story. The concept was used before. This did not discourage me from watching it though. One can use mediocre concepts and turn it into gold. I first saw this aspect as gold. This view, however, devolved and the story slowly but surely turned into something else: A screwy and awkward one. An interesting story suddenly became VERY awkward and weird. Suddenly, it's like the other characters lost their competence and some even derailed into "dreadful and annoying" (I'm looking at you, Yuka.) And the rest just got... blah. I'll give it a 4 for managing to be really interesting early on.
Art - 7/10
11eyes definitely has great art. Arts from other more complicated series cannot be compared to this one since its main focus was the "moe" aspect. Characters that have cute traits like big eyes and the like are found in it. Some battle scenes did look a bit awkward though. At one time, I was expecting an epic fight between two master swordsmen. It shifts to one scene. And then cue to a scene where one of them says "She's too strong." and don't fight anyway. It's like they ran out of budget to make a big fight scene. That was fail. This gets 7 for being really good at what the art's supposed to be.
Sound - 9/10
The opening "Arrival of Tears" by Ayane and "Sequentia" by Asriel are suberb themes and are actually VERY addicting. The BGM of the show, too, was great. Epic music was around. This gets a 9.
Character - 6/10
The characters are stereotypical, that's for sure. The characters were made to cater to your fetishes. This was ok, I understand. It was the point. And then IT happened. One of the main girls degraded into a sick little girl with her own sick little fantasies. And as I said earlier, suddenly most of the cast became incompetent in combat and the main guy just became central view of the show. What the heck happened? This gets a 6 for me.
Overall - 6/10
11eyes, though deserving lots of the flak from our fellow watchers, is a pretty ok anime. It barely crosses "5" territory, which for me is a low score already. Overall, 11eyes cannot be considered a great or a superb anime. But undeniably the show is decent enough to stand. But if one looks for story and development in an anime, 11eyes is not for you.