This is my opinion, but i think mihawk is extremely boring, i know there is stuff behind his character but for now i find him boring, just like i know kaido has stuff behind his character(and im sure you do too since we barely know anything about him still) but he is boring and just complete ass to me rn.
Kaido is definitely trash lol
I literally don't give a shit about him.
But with Mihawk he has some complex layers to him
-Mihawk is "suffering from success" kinda character arc. His motivation is to finally find someone that can kill his boredom, after Shanks has lost an arm and is not strong enough to do so. There are other characters in anime like Saitama with same kinda archetype.
But that's the most obvious one but even beyond that, Mihawk statements like the ones against Zoro to motivate him, his true distance statement and then his statements against Luffy leave a massive room for interpretation which is interesting. Then there is the fact that behind very tough exterior he has soft spot for Perona and Zoro, which could be result of him evolving as a character in Zoro fight. So in turn its not just Mihawk who changed Zoro, made him more serious, Zoro also changed Mihawk.
There is more to that but I am kinda multi tasking rn, I am also clocked in at work. I can make a proper post regarding Mihawk some day.