Problem here is, IMO, Jiraiya is the only one of these three with a true end-game technique.
Orochimaru does have Edo Tensei, but that requires him to have prepped for the battle before hand/to have sacrifices. Everyone brings this up in a debate with Orochimaru assuming he can just use it without having any sacrifice. He's got Yamata as well, but it's pretty much featless and most top tier characters have ways to combat it.
Tsunade is ridiculously hard to kill, obviously her strength is out of this world, and Katsuyu is difficult to deal with, but again these are all things that top tier ninja can deal with.
Jiraiya, on the other hand, through Fukasaku and Shima, has Gama Rinsho. If they synch, it's game over. Clones won't save them because their real body is going to be close enough to hear the melody too(and it's noted to be able to effect several hundred enemies), if they manage to figure out what the technique is and they have futon abilities, they MIGHT could cancel it out, but that's relying on Jiraiya not doing anything to stop them, and again, them actually having knowledge of it.
So ultimately, for me it goes:
SM Jiraiya > Orochimaru = Tsunade > Base Jiraiya(I wouldn't even want to get in to a debate of Oro/Tsu just because of how ****ing frustrating they are to kill.)
If it's any condolence, Jiraiya has to rely on "borrowed" powers from Fukasaku and Shima to surpass them, but that ultimately does allow him to do so.
