I voted Carter, but you've all made compelling reasons for other choices. Having read all the books(Even the newest ones, which are really good. Post war stuff if u were on the fence about Broken Circle which isn't technically post war but u know, Hunters in the Dark or Last Light, give em a try if you haven't already), Reach is a bit of an oddball. So obviously I just based it on the game itself, I found Carter sad because he was our Squad leader and given the way the Spartans look to John especially, but Fred and other S.Leaders also, that was a tough loss. I found Kat bad just because well, she's a girl and was so helpful and capable with everything they encountered. Okay they are all sad is my final choice I suppose, lol.