I don't think Kaido or Big Mom were particularly renowned for their Haki.
Sure, Big Mom had a permanent CoC barrier (which explains her defense), and Kaido has Future Sight and Advanced CoC, but neither of them really had Haki that made you go, "Wow, Kaido's Haki is insane..."
They were known more for their physical power, their durability, and their Devil Fruits; since they rely on Devil Fruits and immense natural toughness, their Haki isn't quite at that same elite level. It’s the same with Oden; like Kaido and Big Mom, he’s known for his durability and incredible power, but his Haki was never really considered exceptional. Plus, Oden suffers from the "flashback effect," so his feats end up looking shockingly weak.
Gaban, on the other hand, is a pure all-rounder, incredibly fast, incredibly strong, and a master of Haki, to the point where he can spam lightning bolts. The trade-off is that he doesn't have a Devil Fruit or the extreme durability of someone like Kaido or Oden.
That doesn't matter, though, because Gaban's AP is strong enough to defeat people like Kaido or Big Mom.
In terms of feats, Gaban doesn't need to shy away from them; in fact, I’d say his AP is significantly stronger than Big Mom's or Oden's.
It actually makes sense why Shanks could one-shot Kid and Killer while Big Mom couldn't.
Shanks is clearly over the other Yonkou like Big Mom or Kaido.