I feel like once Leeteuk goes off for his military service in early 2012, Super Junior won’t be as good as it was. To me, Leeteuk was the one who kept everyone together, even the members said that with Leeteuk gone they have no one to mediate their arguments and stuff.
Out of everyone who is currently active in Super Junior, I feel like Yesung is the best choice for leader (not just because he’d be the oldest and is the leader of Super Junior KRY, but because he seems the most rational to me) but I have this huge feeling that SM will not let Yesung be the leader. SM already told Yesung to never stand in the middle for album pictures and things similar to that, so it’s obvious they think he isn’t that handsome and of course they would want a handsome man for leader.
Besides Yesung I think Heechul would make for a pretty fine leader. Sure Heechul is silly, but Jo Kwon is just as silly (or even sillier) and he’s running 2AM perfectly fine.
If Yesung won’t be the leader, I’m worried for who will be. I feel Shindong would be leader, but he seems he would be a little lazy. Donghae… ehh maybe he would be. And I can’t imagine anyone else as leader.
Even though Leeteuk says that he will get them to reach the top again once he returns from his service, I feel like they will never be the same.
I think they won’t pick the temporary leader. But the one who has the leader ability is Yesung. Beside the reasons you have said, Yesung did a good job to lead the other members when Teuk was in the hospital (Car accident 2007). Heenim said in a variety show (Is it X-man? I forgot T-T) SM won’t pick him to be a leader because the group will be a mess or something and I think Heenim doesn’t really like the idea of him being a leader, but he will take a part of leading SJ when there is no Teuk.