I just finished this anime today. What a ride it was. I loved almost everything about it from the characters to the beautiful art. Everything is hand drawn and cell shaded, I believe. This anime has so much soul. Beautiful score as well. Has one of the coolest mecha fight scenes at the end of the anime that I have ever seen out of all the anime I've watched. All of the characters flesh out throughout the show, even the side antagonists that you wouldn't even think would have a written story. Everyone has their own motives. Not a single poorly written character, in my opinion. I had some problems with Hitomi but she eventually grew on me. Another problem I had was with the romance. Some of the character's decisions did not make sense to me at all. Now to move on to the most important part of the show, Merle.
Merle is a miracle of the universe. She is the cutest character ever to grace the medium. She's wonderful in every aspect and anyone who says she added nothing to the plot can screw off... Without Merle I don't think I would have been so attracted to the anime in the first place!
tl;dr Merle is beautiful and she is amazing.
