Colonel Moore has a serious way of doing things i.e blowing up the brotherhood. While the General Lee is not evil, he is the reason the NCR haven't gotten any further in their main mission: to get the Mojave annexed. Also, I think I'd like working with Hsu more than Moore, (get it?) who has the right idea but is backed only by the General's current position. Also, the selfish Mojave residents are ungrateful for what the NCR is trying to do for them. They are the only force who is fighting their greatest enemy for the greater good of their citizens as well as to look good in the eyes of the people of New Vegas. Even though they are not perfect, they are the best choice for them.