Zoro has so many good possible match ups this arc:
1-Kaku: They had a great fight in Enies Lobby, Kaku was the first person to face Asura Zoro.
2-Kizaru: Kizaru tried to kill Zoro in Sabaody, and almost did it if not for Ray's intervention.
3-S-Hawk: Doesn't need an explanation.
Not to mention, he could possibly meet Kuma on egghead, who gave Zoro one of his most iconic moments in thriller bark.
The real question is, how much of this will Oda use for Zoro ?