I think there’s far more of a difference between being Oden’s son and being Mihawk‘s clone.
A clone should grow in the exact same way as the original, a son doesn’t necessarily do that. And Mihawk > Oden anyway.
For the DF, yes, Momo has a better one. S-Hawk basically only has one because the plot needs him to. But simply having Kaido’s DF doesn’t mean he will become Kaido. What it guarantees is a hybird, an animal form and the bonus of dragon scales.
Dragon scales is explicitly worse than Lunarian flame defences.
The animal form, I don’t think is all that useful. Remember, no one was overly impressed with Dragon Kaido, it was base and hybrid that was good. Like, Boro Breath is something S-Hawk should be able to deal with quite easily, assuming that Mihawk can cut fire like Zoro. Which, as the WSS, I assume he can.
The boost is hybrid, and tbh, I’m not sure that’s enough. That’s an all round boost to physical stats, which is decent. But S-Hawk should have top tier physicals by itself, plus a super durable mode and a speed mode.
I really only see Haki as a potential gamechanger.