I just thought that they were after a child on the flight, they thought it was Aaron but the child ended up being Walt, hence why they let Claire go. Also don't forget Danielle scratched Claire. Did she play a part in it or did she meet Claire after she was released.
And I thought the episode this week was good. At least the season is moving forward. People who are bitching about it moving slowly are just being impatient. If they just told us in the first episode what the bunker was all about and who the others were, what would be the point in watching? Besides clearly they are going to try and milk it for multiple seasons. In the first they had to make sure they weren't cancelled so they sped it up. Now that they know they can have at least four if they wanted, they are going to space it out.
Just think of it like a wrestling match. You start a good match up slow and build it up to a spot. If you have a high spot into a table spot in the first 30 seconds you've killed the crowd off