Great analysis, and one that I think might be right on the money. Might. It's hard to tell with that ending (look, it's not a bad ending, I just feel that it is a bit rushed is all).
However, the greatest realization I had when watching the video, was about the choices that you make throughout the game, which leads you to believe that they will have some kind of great impact on the ending, but in the end are just there to mess with your expectations. Because for as much as the choices are being painted as black and white, there actually one choice which threw me for a loop, and made me ponder which decision was the "right" one.
The choice in question: whether you shoot Cornelius Slate or let him live. Normally, this would have been a cakewalk; killing is EVUL, and thus you let him live as an act of G00D (and instead leave the old coot to rot in a museum, which is just so nice of you). However, there were two things, two simple things, that made me question that decision.
1. Cornelius himself asks you to kill him.
2. The choice where you kill him is positioned where the "good" options normally are.
...
The simple act of placing one choice where it isn't expected to be in a dialouge option made me question what was the "right" choice.
Food for thought...