I dont know bro, I have this issue with him being above Roger because it would invalidate Luffys dream of surpassing Roger if there is already someone stronger then him running around. It just doesnt make sense narratively.
My opinion is slightly different.
Luffy's dream has to be bigger than Zoro's, that much I must agree with, but on one hand we have:
- Luffy's secret dream that the crew and his brothers knows but we don't, that surprised everyone even though they already knew he wanted to be PK and surpass Roger, so it's something beyond Roger.
- Roger "failed to be Joyboy", no disrespect to his character, but by surpassing Joyboy and defeating Imu Luffy will surpass people even greater than Roger.
That leaves Mihawk room to be stronger than Roger but still not top 1 in the story.