I'm surprised we're up to episode 12 already. And I'm disappointed that the season is so short. I've gotten used to Cartoon Network shows having 26-episode seasons.
I'm not crazy about the whole lighthouse/asteroid-barrier thing. The cosmology is ridiculous. Guardian space is supposed to be huge, encompassing whole galaxies. There's no way there could be a solid border that couldn't be traveled around. If there were such a large cluster of asteroids all in one place, they'd coalesce into a single planet soon enough, or into multiple planets, so they wouldn't form much of a barrier.
I mean, sure, there's room for fantasy in fiction, but it seems to me that shows aimed at young viewers should strive to be educational. Science fiction can be a very good tool for teaching the basics of astronomy, physics, and the like, and I think it's a missed opportunity when SF kids' shows misrepresent such things so profoundly.