I just wanted to bring this up, the general opinion is, Luffy doesn't defeat Kaido, and Kid and Law are around the same level, and Kaido and Big Mom are pretty equal too
So
One Luffy doesn't defeat one Kaido
Two Kids do
That means if we put Kid's strength as low as it can be when making sense of this, that Luffy is at least a bit under twice as strong as Kid
If you're ok with Dragon Ball Z spoilers then you can continue reading, this will spoil the power of the Buu saga:
So in conclusion, Kid, and Law too since he is around the same strength level as Kid, is a better rival to Luffy, than Vegeta is to Goku, in DBZ
So
One Luffy doesn't defeat one Kaido
Two Kids do
That means if we put Kid's strength as low as it can be when making sense of this, that Luffy is at least a bit under twice as strong as Kid
If you're ok with Dragon Ball Z spoilers then you can continue reading, this will spoil the power of the Buu saga:
Goku with SS3, his best transformation then, is at least 3 or 4 times stronger than SS2 Vegeta, which was full power Vegeta at the time, assuming their base forms are equal, which, seeing as SS2 Vegeta vs SS2 Goku seemed pretty equal, they probably are
So in conclusion, Kid, and Law too since he is around the same strength level as Kid, is a better rival to Luffy, than Vegeta is to Goku, in DBZ
