I'd say watch the pilot (and perhaps S1 finale if you're nervous) but then move on to S2. Seriously. So many issues with this show. I mean I love it, but S1 is all over the place. ALL OVER THE PLACE. IN A BAD WAY. S2 is all over the place but in a good way, and there's plenty of gay and of awesome backstory.

Also, Children of Earth? First three episode are the most glorious three hours this show has ever done. BUT MY FEELINGS ON THE OTHER TWO ARE SO CLOUDED BY PAIN STILL. But watch it. It's so entirely worth it.