Since we know:

oro is about same strength as 3rd (if it takes them 10 ep. to finish a fight, they can't have much of a discrepancy)

itachi is stronger than oro (oro said so)

jiraiya is stronger than itachi (itachi sort of made it clear but it is still technically an assumption, because I am accounting for the fact Itachi might not b in his best condition, just a guess when kisame told him not to use his sharingan too much).

so we have:

(oro, 3rd) ------> itachi --------> jiraiya

since 4th is dead, I was wondering where you guys think Tsunade is on this comparison list

I guess she is most possibly between itachi and jiraiya, or maybe only itachi level. My reasoning is the counsel old man and woman that asked jiraiya to be hokage had to give it a LONG thought before rooting for tsunade, meaning true strength wise, jiraiya should be stronger.

What do you guys think?