Well, if Big Mom stops chasing Usopp's and Chopper's ass, there could be a low possibility of Big Mom fighting Luffy, a LOW POSSIBILITY since this is not Big Mom's arc, it's Kaido's arc and he is obviously the arc boss.
Who says it's "enough" for him? Like, are you really that stupid bro?
Yamato does not seem like an antagonist but okay, if you think slaying Orochi is better for Zoro than beheading Kaido, it's fine.