Story. I think they really miss this one. Usually the Story revolve around the MC, but they only scratch it. They tease about each MC backstory but give a full story about it. I hope they wait for enough material from the LN to make it a 25 episode/2 season. It's like watching the first SAO and end it at Aincrad Arc.
Art. Tomose Shunsaku, if you play some VN or eromanga you might know this person. I got to say the art is very good.
Sound. There is really nothing worth mentioning.
Character. Each of the MC have pretty interesting history, and some...twist.
Enjoyment. You should probably watch it in one go. The story is pretty slow and there is no interesting episode. Most of them relied of next episode explanation about what the hell happen in the last episode.
Overall it should be a good anime but they rushed it and just destroyed potentially a very good anime. If you're haven't watch it, I recommended to hold it and wait the 2nd season.
