Had Madara had time to be in his Juubi form and 3 eyes

[super michael]

How powerful would have Madara have gotten if he had time to train in his Juubi form? Madara when he awakened his Rinne-Sharingan he was able to use IT easy.

Madara has more knowledge, intelligence and experience than Kaguya, so I believe Madara has the potential to surpass Kaguya had he not being back stabbed by Black Zetsu.

Kaguya has lot of powers but hasn't shown much intelligent.

 

[SenseiSama]

Even if he had time he would never be able to use anything other than IT. The chakra required to use Kaguya's dojutsu is too much for Madara's body to handle, he'll just end up exploding again

 

[Scryed]

He can't contain the amount of chakra required to use RinneSharingan. He can only use IT whose purpose is to increase chakra reserves but that'll make him expand again. Only difference here would be that he would explode instead of turning into Kaguya.

Databook gave her some intelligence since apparently she had complete mastery of chakra and BZ was following the orders she has given him if I remember correctly (I don't know if it was a mistranslation though). Regardless, she's obviously less intelligent than Madara. Not enough to make up for the difference in power though.

 

[Rikudou Tobi]

Even if he had time he would never be able to use anything other than IT. The chakra required to use Kaguya's dojutsu is too much for Madara's body to handle, he'll just end up exploding again

This pretty much ends it. Madara's third is just kaguya manifesting her ocular doujutsu through Madara's forehead.

 

[Holy God]

Madara would have been far more powerful than Kaguya. The Databook says with the Holy Tree he becomes able to combine all chakra and Hagoromo warned Naruto and Sasuke about stopping him before*he ate the new Chakra Fruit, so chakra isn't a problem since Black Zetsu isn't in the equation.

 

[Shruikan]

Madara would have been far more powerful than Kaguya. The Databook says with the Holy Tree he becomes able to combine all chakra and Hagoromo warned Naruto and Sasuke about stopping him before*he ate the new Chakra Fruit, so chakra isn't a problem since Black Zetsu isn't in the equation.

He wasn't able to handle all that chakra which is why he inflated like a balloon

 

[Holy God]

He wasn't able to handle all that chakra which is why he inflated like a balloon

He couldn't handle that chakra because Black Zetsu took control of his body. Hagoromo specifically warns about stopping him before he ate the fruit, which would subsequently give him more chakra than Kaguya had.