Combat experience is the major difference between Kaguya and Madara. Kaguya had more power, but I think Madara would of given them a better fight. Kaguya was basically the equivalent of a toddler with a rocket launcher, she had all that power, but didn't know how to utilize it to the fullest extent, this is why black zetsu was ordering her around the whole fight he was basically her brain. JJ Madara on the other hand had less power, but wayyyyyy more skill and actual life and death combat experience. If he was unrestricted which means he uses all the rinnegan abilities plus large scale mokuton that makes hashirama's look puny there's not doubt in my mind that he rapes Naruto and Sasuke.
I remember in an interview kishi said he didn't know how to defeat Madara, so in my opinion, one of the reasons he introduced Kaguya was because her lack of skill and experience makes her an easier fight than Madara. He can justify team 7 defeating Kaguya more believably than them defeating Madara. He wouldn't allow the manga to end with Madara ruling the world after all. Even though that would of been ballsy as hell lol.
I remember in an interview kishi said he didn't know how to defeat Madara, so in my opinion, one of the reasons he introduced Kaguya was because her lack of skill and experience makes her an easier fight than Madara. He can justify team 7 defeating Kaguya more believably than them defeating Madara. He wouldn't allow the manga to end with Madara ruling the world after all. Even though that would of been ballsy as hell lol.