Maybe, maybe not. For Rykov, playing professionally in the KHL doesn't necessarily mean anything about your ability to play in North America, so I'm unmoved by that. And while Hajek is a second year pro, he looks to me like he had taken a step backwards. So, I don't know, I think Miller's game is currently better--or at least as good.Not saying their defense is good. Not saying I’d trade any of them for Miller (not even close, I said right above how exciting his potential is). But Hajek and Rykov have played pro hockey for several years now.
They struggled in the pros for a time, while Miller struggled in college for a time. As it stands right now, both are better defenseman than Miller, by a decent amount.
Unfortunately, we may have to wait until next season to find out.