Me, too. I assumed originally that the adults would either stay up in space as background characters or get killed off by the end, but then they focus a lot on them. I found Marcus Kane the most interesting of the adults but he didn't get the story arc I'd hoped for in season two. And as interested as I was in seeing Abby and Clarke interact in the eps I saw they spend very little time together (Clarke gets a whole storyline off with the Grounders instead). The adult it mostly focuses on is Jaha who I disliked the most.

*SPOILERS* The kids get taken by the Mt. Weather people and there's a teenage girl there named Maya who Jasper ends up becoming friends with and eventually a romance. She doesn't get to do much, unfortunately (I slightly hoped she'd be evil just to make her interesting), although she does seem to want to help when the other Mt. Weather people want them dead, and she ends up dead before the end of the season.