Think about it this way...how many people d'you think just threw their controller against the wall at some point through FF4, and just said " it!" Then, the whole ending, and a lot of story is lost to them. Easy final bosses mean that you get to see the whole (Or at least most of) the story fairly easy. I mean, a good challenge is good, so I presume that's why they added the Ultimate bosses. I liked Kefa's battle, though. Easy enough to be possible without INSANE levelling up, but tough enough to still pose a challenge.