Law likely had help against Hawkins. The 1st clash Law and Hawkins had Hawkins held his own against Law really well. Hawkins the next time around didn't even have any lives and may even have gotten jumped. How can you say Killer's a joke? Sure Zoro may have trashed him, but that's because he Zoro, the oneshot champion. Santoryu isn't a joke. Now Kyoshiro was likely holding back, but Zoro was injured and only had 2 swords.
Zoro doesn't have fears in terms of accomplished enemies he's defeated, but he does have the frats in terms of DC/AP, arguably portrayal, and bear in mind that Zoro oneshotted everyone thus far with relatively weak attacks and still hasn't used his EL power up, so he's holding back severely.
Zoro and Sanji will likely be leaving here as YC level crewmates at the least. There aren't that many obstacles to get over after this arc and therefore will need to be way stronger than what they have shown thus far considering that after Wano there are only that much closer to becoming a Pirate King Crew.