Confirmed, non-debatable FACTS; that are still denied by some......
"This Susanoo is destruction-incarnate, everyone who has seen it, has died."
This proves Uchiha Madara had the Perfect Susanoo long before he attained the Rinnegan, hence...his EMS version is all that he needs to stabilise and Perfect his Susanoo.
"Yata no Kagami for defense, Totsuka no Tsurugi for offense, he is invincible".
Black Zetsu, the will of Uchiha Madara himself, who pertains all of his knowledge and original decisions, deemed the combination of those two weapons as invincible, hence.....the bearer of those weapons is invincible.
"I told you not to open your mouth so easily! You're just words and no actions, what someone like you says is worth nothing!"
Yes he has a great personality, yes he tries his very best, yes he is loyal to his village and yes.....he is super smart and elite! That still doesn't change the fact that Kakashi has never kept his word or promises, whether due to extremely bad luck, hesitation or pure lack of chance......Kakashi's words are not worth much.
"He was known as the God of shinobi!"
Even though we haven't seen it, and many people don't want to believe it, Sarutobi Hiruzen, in his prime, was the strongest shinobi to have ever lived. I have put this fact here because Kishimoto himself has confirmed it and it is certainly believable seeing that a 70 year old Hiruzen who had lost most of his strength and chakra to his old age, sealed away 2 former Hokage, Senju Hashirama and Senju Tobirama, took away all of Orochimaru's jutsu, putting a dent in his plans for years, and leaving him whimpering and screaming like a child, at 70! Edo Madara is not included in this because he is just a soul wrapped in dust and earth and not a living breathing human.
Edo Madara is the strongest being!
Whether living or dead, natural or abnormal, he has unlimited chakra, an indestructible and regenerative exterior, Mokuton, EMS, Rinnegan, Perfect Susanoo, years upon years of battle experience........Edo Madara is the strongest thus far and there is no denying it!