I agree about Sean- the ending was just sort of "Yay! Everybody wins!" and I was left thinking "...except Sean."
They were also very casual about the parallel reality part- if they're all their own whole universes, it's pretty messed up. I liked it much better if I thought of them as little bubble universes that either popped or rejoined the main universe, but that wasn't so much textual as my choosing something possible that I liked better. Especially since it worked better if we're going to think he actually changed anything, and didn't just shift to a new universe, leaving the original one behind.
Also, as source code gets used again and again, are there just going to be more and more doppleColters wandering around? Because he's still in the source code at the end of the movie, too, because in the ending universe, whether that's the changed original or a new one, it never gets used, so Goodwin never turns off his life support.
Spoilers in this comment, too.
They were also very casual about the parallel reality part- if they're all their own whole universes, it's pretty messed up. I liked it much better if I thought of them as little bubble universes that either popped or rejoined the main universe, but that wasn't so much textual as my choosing something possible that I liked better. Especially since it worked better if we're going to think he actually changed anything, and didn't just shift to a new universe, leaving the original one behind.
Also, as source code gets used again and again, are there just going to be more and more doppleColters wandering around? Because he's still in the source code at the end of the movie, too, because in the ending universe, whether that's the changed original or a new one, it never gets used, so Goodwin never turns off his life support.