1) sounds good. probally Jiraiya's point of view.
2) boring~~~
3) Zabuza is dead long time ago so... maybe kisame if hes still alive
4) most likely some sort of flash back from itachi when he faces the new sasuke.

I would love to see more kakashi gaiden. since we dont know what happened to rin and how kakashi developed the 3 commas sharingan. It will be great if its something other than: "kakashi is powerless against some dude then rin jumps out saves kakashi and then blah blah blah..."