They're not as similar as we may think.
First, Roger is more responsible than Luffy regarding his ''mission'' and ''destiny'', while Luffy couldn't give a damn about that.
Second, he was way more cruel than Luffy, just remember what he did to Squardo.
Yeah sure, the crew whose captain paralyzed aramaki while not even being on wano proper will struggle against him in a '' serious fight ''
The copium here is really some gourmet shit :steef::steef::steef: