Ah, Eureka Seven AO, how I was so excited to watch you before you aired. Now here I am facepalming all over the place at how bad this show is, and how I was foolish to be excited for this.
Let me start out by saying, the original Eureka Seven is one of my all-time favorite anime series, and it's just sad for me to see what BONES did. They are merely marketing a show purely based off of nostalgia, and putting zero effort into it, less so than those incomplete adaptions used to sell more of the source material.
So first off, what is this show all about? Well originally it was about Ao, Eureka's son as you probably could have guessed from the promo image, joining a group called Pied Piper-actually, just a subsection of Generation Blue-(The E7 AO equivalent of the Gekkostate, not.), and trying to find his mom (Who he calls "Anma!"-Where did this shit come from?). From there, it's total nonsense, especially in the second half. Seriously, I doubt even BONES knows what they're writing in this show. Hell, it's even hard to review this show because it's so messy. So where did it all go wrong?
Part of the problem is how Eureka Seven had a completely closed ending, with no loose ends. So, what the heck were they supposed to do for a story, a sequel story? Set it up in our world, instead of the world of the original E7? Introduce an overpowered villain with no motives, and then come up with something along the way? Put in terminology the viewer is completely unfamiliar with, and explain it midway when all the characters knew everything from the start, and assumed the viewers were the same? Put random things in, and forget about them completely in only a few episodes, making it completely redundant? How about just put in random crap to fill up 24 episodes? Really, these are warning signs the show is going to be a total mess.
There are tons of plot holes everywhere (Especially in the final two episodes which are just one large Deus Ex Machina), and lots of things will not make sense as such. In one instance, it's stated everywhere the Secrets are not the enemy as they merely take an element called Quartz away from the Scub Corals. But then later, Generation Bleu tries to eliminate all the Secrets. Oh and let's not forget how you can travel around the world in only an hour, it doesn't matter where. Seems the earth is way smaller than it really is...
How about the characters? Did the characters turn out good? Hardly, the show makes some of the same mistakes Shakugan no Shana III (Final) made. It introduces a bunch of characters, and then doesn't bother to develop them, or show any backstory, so they're just...there. Many characters will develop in some way, but it'll either make no sense, or it'll be a total character rewrite. We'll also get some good backstory, but the show then tosses it aside and forgets about it. The backstory rarely ends up being relevant to the story.
Lastly, can we forget how they introduced certain elements you never in a million years wanted in E7? An otaku girl? Moe girls everywhere, resulting in a harem practically? Fanservice? And what purpose does this serve? Really, what does it serve for a good story? In this show, it can't co-exist with the story, and character development like does in various shows.
Really, they should have either made this not a sequel, or took a page from Gonzo from when they made Last Exile: Ginyoku no Fam, the sequel to Last Exile which also had a completely closed ending. That show managed to do a much better job at things, from the story, to the characters. It did not rely on purely nostalgia to tell a story, and the result wasn't all that bad.
Eureka Seven AO in the end is a prime example of doing everything wrong in a show, and what happens when a studio uses only nostalgia to tell a story. Take the E7 fanboy glasses off, and you'll immediately notice the many, many problems. One can only hope less of these kinds of shows get made in the future. Nostalgia can be great, but not when you use it to tell a story for a show.