Sasuke overall for me, but i still like Madara's limbo clone tech
Madara. Look at his Katon compared to anybody elses in the series. His Mokuton was on Hashis level. He summoned meteors in the blink of an eye. Limbo. Madara was just God-like. If Kaguya and her sons werent in the series, he'd be the strongest.
He's the strongest in the series as a host.
Kaguya and her sons are still more powerful. Madara maybhave shown more techs and abilities but thats because the others werent shown that much.
Madara is #4 to me. Kaguya, Hagoromo, Hamura then Madara.
Since Hagoromo doesn't know nin-jutsu to do any damage, and Hamura was never a host so he's nothing exceptional, then the only option is Kaguya. She doesn't have much battle expertise, so I place Madara on top. He was so strong Kishimoto had to find a way to defeat him(Kaguya).
Look at it this way. A ghost of a Hagoromo way past his prime and jin status gave Sasuke and naruto his power. That power was able to beat Madara. So with that Hagoromo > Madara.
Hamura was able to help his bro fight and seal the juubi which puts him equal or a tad weaker then his brother.
Kaguya was the strongest in the series. She > any individual . Madara is strong but there are 3 stronger. Well thats my opinion. Yours can differ