I actually am not sure to be honest. And I'll explain why.
If Luffy and Zoro were just the PK and his right hand man, like Roger and Rayleigh were, then I would definitely say the WSS. When I say just PK and his RHM I mean if they were to do the same thing as Roger and Ray, that is discover Laugh Tale and OP and not be able to overthrow the system that oppresses people, the WG. However, the thing is, where Roger and Ray failed, Luffy and Zoro will succeed. Luffy and Zoro will overthrow the WG and free the world. They will be hailed as saviors, like they are in multiple countries thus far.
Why I pick the WSS over just the RHM of the PK? It's quite simple imo. Zoro would be what Ray was just by being the rhm of Luffy's ship. However, there's a difference between Zoro and Rayleigh. Zoro has had a life long ambition of becoming the WSS.
Ever since he was a child he has had that drive to sail the seas and become the strongest
He has always had a clear cut goal and drive to achieve his goal and become the strongest one day
He vowed to become so strong and renowned as a swordsman that his name would be famous in heaven itself
Compare that to what we know of Rayleigh. When he and Roger meet Rayleigh is living in a stolen ship, anchored at some unknown place, because his house burned down.
He isn't doing anything like Zoro, who was actively seeking Mihawk and beating people on his way to his goal. He was just chilling somewhere, without a care in the world, and without any hint of any ambition or goal in his life.
To further illustrate this, when Roger tells him this is a meeting of fate and they should turn the world upside down, Ray's first reaction is to tell him to get lost. Basically, Ray just wanted to chill there for as long as he could, without a care in the world.
Which is also further emphasized by the fact that when we meet Ray he is basically doing just what he had done before joining up with Roger. Keeping a low profile on some island, drinking away, gambling, banging chicks, stealing, enjoying life and just waiting for his death. However, upon meeting Luffy, Zoro, and the rest, he has found something to look for, something that would make him wanna live life again fully and see with his own very eyes what will happen.
That imo is the difference between Zoro and Ray, and why the WSS would trump the just RHM of the PK. However, as mentioned above due to the fact that Luffy and Zoro will do the unprecedented, makes it a bit difficult for me to to say which one would garner Zoro more remembrance.