7/15's episode was really good. The characters are so much more appealing when they are acting with reasonable intelligence(Tom screwing up then apologizing immediately was nice). The writing seemed sharper, giving a lot of specific details about the 2nd Mass' situation that helped make things seem more grounded. The fuel situation, ammo, food, all that stuff needs to always be an ever present worry for our heroes, and it was nicely incorporated here.
The ambiguity with Karen was nice, and something that needs to be used more in the show. For all of the first act, and part of the second(right up until they started giving Karen deliberately ominous shots) I was unsure which side she was on. However the overlords ability to control human subjects, with full access to their memories and personalities, as pawns is something that had better be remembered by the 2nd Mass. They need to get more paranoid real fast or start looking like idiots again. And it further adds to the problem the writers keep running into but not really addressing, which is how aliens who are so powerful and technologically advanced can't seem to keep track of(or wipe out) a couple hundred humans who roam around in diesel trucks. These are the same aliens who wiped out billions of people and every military force on the planet?
But overall I really like that the show seems to be improving in both plotting and characterization. It seems very possible that the second half of this season will be better than anything they have done so far.