How much of a boost up the rankings does Marco's fruit give him?

[Warmmedown]

I imagine he can handle fighting someone stronger than his level of speed, power and haki, due to his regeneration. Even if he's weaker than someone, if he's strong enough to hurt them, they'll eventually accumulate enough damage to be defeated, while he stays pretty fresh. Also if he has enhanced stamina (idk) he could win due to that.

Even if he's haki-punched, it'll do damage that a normal punch, magma punch or Kizaru laser wouldn't, but afterwards he can heal. So his fruit is one of the least affected by haki.

 

[Future Warrior]

Loses to Zoro, Sanji, Kid, Law, Admirals. His regeneration takes stamina.

 

[Warmmedown]

That's not the question. How much does it boost him above someone of the same general strength, but without regeneration powers? Or in other words, how much weaker would he be in battle if he had no regen?

 

[Future Warrior]

Without regen he loses to Katakuri cause of his FS. He maybe still beats King, cause his attacks can damage him, but hard to say if it would be enough to beat him.