She may be weaker than jiraiya and oro but I belive she is stronger than kakashi. I mean she is one of the 3 legendary and is obviously on Hokage lvl, And kakashi, yes he is strong but he can't beat oro, And was badly defeated by itachi.

about kaubo, I belive he is stronger than he appears to be, he may even be stronger than kakashi.
but his intentions is hard to see, allthough he is loyal to orochimaru it also looks like he would betray him anytime.
well there is just one thing way to find out..
to wait and see