Would you please wrap the Axel part in Spoilers?
(SPOILER)And no, Axel's death had a use. If he had survived the end of the game, that would have undermined the quest of Sora and the party, as an Organization XIII member would still be alive, whether or not he was willing to help Sora in anyway he could to help Roxas. This would mean that Xemnas would still be both unapproachable, and he would have an existing agent to act through, as Nobodies have the ability to control other Nobodies. Xemnas (the Superior) OBVIOUSLY shares this trait. Sorcerors are stronger than most of the other OXIII members, yet he controls them. What influence he might have had with Axel!
Sora's alright. I have nothing against him. I respect him because he gets to go home with Kairi.