It may not seem like everything didn't worked out in the end, especially with Ed in our world and Al in the brother's homeworld... But, as you said, the worse threat is gone and that, alone, makes everything else seem a lot better by comparison... However, in Brotherhood, the worse threat is not only gone, but literally everyone [still alive] gets their "perfect" ending/conclusion in the long run one way or another... To me, the original has that glimmer of light at the end of it's tunnel while Brotherhood never had that suppose darkness in said tunnel to begin with in comparison to the original...
