i still don't like the GN particle shield... I never really liked 'energy shields'. I suppose my problem with them is that they make the gap between the Gundams and regular MS even wider, something I don't think they really need to do... must be pressure to make the Virtue look cooler for model kit sales...
I don't know how much time Ali spent with Setsuna, but it looks like he proved to be a very good conman in recruiting him as a child soldier... Him seeing Setsuna in how he pilots the Exia is a stretch, but it's anime stapler for connecting characters when one has a secret identity.
Also, Setsuna's comment about "If that is Ali, where is his God now?" I couldn't tell if that was a rhetorical, semi-sarcastic question meant to mean that Setsuna knows Ali wasn't really in Kurdistan for religious goals, or if it's some kind of benchmark that Setsuna sets. Buffalo's comment about Exia being pretty much a god to Setsuna makes me think that maybe his "jihadist" ways haven't changed at all. He simply got a "god" that answers his prayers... so he serves that one now...