Lucci's attacks only need to be threatening enough for Zoro's durability which they are.
No doubt Zoro's high end moves are in a different realm, they literally surpass Top Tiers attacks but Shugan, Rokuougan or basic Tempest kick slashes already would hurt Zoro greatly.
The most impressive thing is that he's trading with Zoro instead of using his agility and make it an aerial battle, raining down attacks from above.