I had better luck with another movie I watched on my vacation, "Flightplan". Nothing in it posed facial recognition difficulties. I think the key was that it had only one person per gender per age category per hair color, if you know what I mean. :-) The two main male actors (the air marshal and the pilot) differed in age by about 2 decades, so I didn't have trouble telling them apart; same for the female characters -- Jodie Foster and two flight attendants. The flight attendants were both young, but somehow it's much easier for me to distinguish between female faces than male, so telling the two apart didn't present a problem. Another advantage of "Flightplan" was good lighting: well-lit faces carry more visual information.
"Flightplan" is a thriller that takes place entirely on a plane. It's an ultimate anti-in-flight movie. Best not to watch it within a week before flying.
I found it more original than most thrillers I watched (which is not very many). It was hard to predict who the bad guys were or what they wanted, or how they were going to achieve it. My only beef with it is that it had a point-of-view problem. Actually, I'm not sure if point-of-view analysis applies to movies as much as to books. In written fiction, it is necessary for the author to stick with selected point of view, i.e. to show the story happening through the eyes of a chosen character. There can be one or more of them, but the author has to be consistent about who's telling the story. I'm not sure how much this applies to movies in general, but "Flightplan" is told very clearly from the perspective of Jodie Foster's character. Throughout the movie we know only as much as she knows. Then towards the end we are briefly shown who the bad guys are and what is really happening. This detracted from my enjoyment. It's as if the authors thought the've confused the audience so much, the viewers won't figure it out for themselves, and need to be shown all the cards.
I think if you are showing both sides' POVs, you have to do it from the beginning. Then it would be a different kind of movie -- it would be about a cat-and-mouse play between the two parties. I actually prefer "Flightplan" the way it is now, a story of a woman who upsets all the norms of socially acceptable behavior, and stands up to people who tell her she's crazy, as she searches for her missing daughter. Not to mention she pulls off very scary stunts as she crawls up into an airplane's avionics section and rampages through it, scaring the s**t out of the airplane's passengers. All in all, a good piece of escapism.