I've had this thought for a while as well, looking back at Kizaru's past actions he always seems to cause anguish both physical and mental. I always think about the scene where he almost hits Zoro point-blank with his light kick in chapter 511.
Like this dude intentionally delays his attack as the other members desperately try to save him. Usopp and Brook can't hit him, and he steps on Zoro to prevent Robin from moving him. The other members look in shock at Zoro's situation. And we know he delayed his attack as he's done this same move much faster before. It's like he wanted to intentionally cause as much dread as possible before fully killing Zoro.
You could probably apply this to all of his other actions as well. I think you're on to something here as this guy for sure has a sinister side that we'll see more of when he gets serious towards the end of the series.