Sorry, but right now I can't post too much except this:
HA!!! I was right!! Power Princess is a traitor because.... She's actually Warrior Woman from the Squadron Sinister!!! I knew it was her because of her swords. This open a big door for Thundra replacing her in the Squadron Supreme.
And by the way, the big enemy in this story is another old Avenger went cuckoo by Weirworld: Doctor Druid!!! (Just like Black Knight).