See, I think that WAS the problem (along with the other Terminator machines and even Skynet itself).
The future in Salvation is quite tame compared to the apocalyptic future of T1 and T2. In those first two films, we saw a rag tag army, kids playing with rats, moaning, and pure agony. That looked like a hellish lifestyle. The future was grim and the cinematography with the blue hue represented that. The crushed skulls, the hopelessness, the fact that everyone was underground and looked like ****, it was nightmarish.
Salvation? It was just grey. It barely looked like there was a nuclear war (despite seeing the actual missiles hit, like in T3). It was more along the lines of Mad Max then it was Terminator. They had gas stations, forests, lakes, helicopters, submarines and everyone looked quite clean and well fed. Connor was even preparing for a friggin' kid wasn't he? It didn't look like a horrible life.
Think back to what Kyle Reese is describing in the first Terminator. "It's gone . . . all gone". Or how he and Connor were in these concentration camps having to dispose of bodies night and day. It was dark and grim and mirrored the holocaust. Terminator Salvation? They cage everyone and put them in these sterile, glass prisons. They don't even kill or dispose of anyone. Skynet isn't even cold and calculating in the film, even when it has the advantage of knowing Connor's past and who is dad is (or atleast, the importance of Kyle Reese). It just sucked.