SOME MINOR SPOILERS
And all the family stuff was completely unnecessary, particularly the final ten minutes, which are all about Tom Hanks the family man getting redemption for doing his job.
I agree with that...I watched it again a couple weeks ago and the final scene on the train bothered me more.
SPOILERSOn the plane back to the US from Germany, after they’ve retrieved Powers in the swap, you have Powers imploring Donovan to believe him that he never talked. Powers needs the public acknowledgment of his integrity because the implication is that he broke under pressure after being captured by the Russians and doesn't have this integrity and peace in private. I don't know the details of the real story, if Powers actually did, but for the movie's sake this seemed to be pretty clear.
In contrast you have Donovan, who has been operating oppositely, tirelessly, and thanklessly, keeping his actions hidden even from his family because his behavior is influenced by his personal moral compass - coming from a place of it being the "right thing" to do.
The last train scene has American passengers reading a newspaper article about Donovan's involvement in the swap, glancing at him approvingly and smiling - different behavior than they displayed earlier on in the film in a similar train scene where they were reading about his representing the supposed spy and firmly disapproved. This second train scene where the passengers turn to his side really fucks up the theme of the movie, giving Donovan the thing Powers needed only because he lacked the integrity that Donovan had - Donovan shouldn't need societal approval given what we've been watching so far. This scene "confirms" that in the end Donovan did do the right thing after being doubted and maligned for his choices, but it weakens the idea that we should live by our own resolve, apart from the tyranny of the mob, even when it's most difficult.
That's my only quibble with this thing, but whatever, it's Spielberg.