I get the feeling Perez was starting to run out of steam with the Bana. As you say, whole lotta questions get raised, few if any answered. But then, you're not posting these exactly in order, and Perez went on with WW for a good deal longer, so . . . maybe he was just sort of having a bad week when he came up with the idea and let inertia drag him along in telling it, not having anything better.
And it all ended a little too neatly, like he was going "Okay, now what do I do with these gals? Ah, just destroy their city, whatever, I'm almost done with this series, let someone else deal with 'em."