Quote Originally Posted by Assertn
No. We were discussing which one Luffy would be less likely to forgive.

Case in the bully point, even if Crocodile killed more people than Arlong, Luffy still has more reason to personally hate Arlong.
You say tomato... if one is more deserving of hatred than the other that would qualify him as less forgivable

Because he hurt Nami? Vivi was also hurt, and in his mind they're both equal nakama