Just to point out, Kakashi's MS is practically useless in battle at the moment. It takes him several minutes to activate MS, a few minutes to aim his black hole technique, and he has difficulty hitting moving opponents accurately.
ZabuzaDemonGod, all three had restrictions in that fight, and it's difficult to really say how their restrictions compared. Kakashi's also strong enough to be useful himself, and I think Tsunade on form and Kakashi will be quite a good combination against Orochimaru. Nonetheless, edo tensei decides everything – I'm discussing it as if edo tensei does not exist as I have no idea who he is summoning.
Who he can resurrect just ends the entire thread. If it's another legendary jōnin, it's game over. If it's anyone who can stall Kakashi, it's game over.
And that jutsu he used cost him a massive amount of chakra. Katsuyu can spit acid that burns through rock, and Kakashi's raikiri has very high attack power. His Mangekyō Sharingan destroys without question. You may doubt that Tsunade can kill Orochimaru, but you cannot doubt that her attacks could wear him out, injure him seriously, and with ranshinshō prevent him from moving ? then Mangekyō Sharingan ends it.Tsunade did beat the snot out of Oro in Part 1, but someone explain to me how Oro can be killed by taijutsu? After his body was torn in half by Kn4 Naruto he literally pulled himself back together.