Kaido would become more elusive/harder to hit (he would be able to open holes on his body to avoid damage, just like Katakuri and logia users do), but would also become weaker, less durable and would lose the zoan's passive regen. His battle against the Ninja-Pirate-Mink-Samurai Alliance wouldn't have lasted that long if he had a paramecia IMO. I think that it would be worse for him, as he's stylistically a tanky character (he just takes the damage like a boss and overwhelms his opponents).
Katakuri on the other hand would be an unknown. Having (probably) eaten his DF pretty early (still as a child, I guess), it's possible that he developed his fighting style around his DF abilities (more elusiveness = better CoO = future sight). With the Uo Uo no Mi: Model Seiryu he would've to focus on his CoA and maybe even on his CoC to become stronger. Perhaps he would be more like his mother and would become a CoC/CoA specialist. However, if he sticked with his advanced CoO only, it could be worse for him stylistically.
