My only criticism in regards to the finale was the handholding. It bothers me when shows decide to do that. Same thing that bugged me with Inception; the constant explanations and guiding the audience took a lot of screen time.
Two prime examples; Even though the camera zooms on the sweetener when she grabs the packet, and then zooms at her for a good minute while she pours it in her coffee, we still get the phone call of him explaining it to her. I didn't mind the call, but he should have just hung up the phone after he told her if she was sick. No explanation needed.
Another one is the gun. We didn't need to see him built it and make it obvious that iot will be used. The episode could have just opened with zoomed in shot on the thing he built. Don't show the gun or anything else. We would all be wondering WTF was that metal thing. And when it popped up and shoots everyone at the compound, the surprise would be 100x more powerful. It was just too obvious that it would have been used at that scene since they showed him build it and show exactly what it does.
Again, nitpicks, but I have OCD so this kind of shit bother me.
Overall a little too nice of an ending, but I respect that. NO forced twists or cliffhangers.