That isn't the impression of the series I have at all. I watched 00 and AGE back to back and 00 feels like the one written for five year olds. There isn't anything in AGE as stupid or vestigial as Nena or Graham Aker or that useless stupid princess. It's an incredibly focused series.
AGE doesn't do anything amazing but I think a lot of people knock it just for the art style. But it can be just as dark and thrilling as other Gundams.
Hateable main character? Who are you talking about? If you mean Flit? He's supposed to be a hateable jerk in the third act, you know.
00 is trash, too, it's just a different kind of trash.
I didn't continue watching the show because I felt like the early episodes were just so offensively bad. The writing was extremely juvenile, and Flit was a terrible, obnoxious character from the first episode. The entire show was a completely cynical attempt to market Gundam at the Inazuma Elven crowd, complete with a main character for the kids to identify with.
It's a cynically created attempt at getting all da kids to start buying gunpla, with absolutely no attempt to actually do anything original or have anything meaningful to say about war except parroting the same things from past Gundam shows. The fact that it was the biggest failure in the history of the franchise, complete with getting a 0.0 in the kids demographic regularly, is one of the most gratifying things to ever happen in the success or failure of anime.