Date A Live has ended, and it certainly the biggest surprise coming out the season for me, based on my lackluster initial impressions of the anime.
So rather than do a full out review -- which is normally spoiler free -- I want to do more of a critique of the series, that will have spoilers, but it makes things easier to explain instead of tippy toeing around important information. From this point on, I will be spoiling things from series, tread carefully.
So the biggest problem I have with Date A Live is the ending was very open ended; it felt like they were relying to heavily on a second season that might not even come. I've seen quite a few anime that do this, and just end up with an unfinished anime or even leave on a cliffhanger.
Now, it is fine if there is a guaranteed that the anime will continue, but you shouldn't end expecting a new season, just close the loose ends -- so it feels more like an ending rather than the end to start the beginning; if there is a new season, introduce that new problem/question there, rather than in the previous season, and go from there.
One of the important unanswered problems, that Date A Live just dropped randomly, was the fact that Kurumi -- one of the only antagonist in this series -- is still around killing, and no one cares. That is an odd thing to leave open if you ask me. It seemed like a lost effort to introduce her, and then drop her so late in the season, for a completely different problem they deems more important. Kurumi felt more like a bigger goal for a later date, the final obstacle for Shidou to concur after all the practice on the small fries -- like Tohka, Yoshino, and even Kotori.
Speaking of Kotori, it was a bit strange to see that bit of pseudo-incest -- since Kotori isn't really his sister -- near the end, like they were checking it off from their list of female archetypes. I'm not outright against incest in a storyline, it has to be done correctly, and Date A Live doesn't deliver from that front.
As for the last thing that isn't answered -- I would consider this to be pretty important, but isn't that integral to the story -- is why is Shido able to seal a Sprite's powers? I'm wonder if any guy can do it, or he is the only one that can, because he is "special". If it is the latter -- which is probably the case, in order to keep the story focused on him -- I think them trying to explain away this fact, wouldn't be that great of an explanation. In order to keep the inner logic of this harem going, Shido must be the "glue" to the equation to produce it's predictable output.
In closing, I found Date A Live was trying to please too much of its audience -- which is what more harems tend to do -- making the story as a whole pretty muddy. Despite that, I did enjoy the series, regardless of my criticisms, but that doesn't necessarily make this a good anime. I would consider it above average if anything, but I am looking forward to the next season, if they do get one.