As someone who would take Hughes over Kakko, there are a ton of things for Hughes to work on. He did create a ton of chances today, but we also saw what makes him very raw.
He tries to outsmart opponents who have the puck by putting his stick in lanes to predict what they'll do, as opposed to engaging physically and dictating the positioning of who he's checking. I get it - physicality is not a strong suit so it makes sense for him to avoid it. But he'll have to get craftier about checking at the NHL level. There's a time to play a blue collar game and it can't always be the last option in your toolbox.
I'd like to also see him follow up his shots more and offer better support to his linemates. His ability to get lost in the coverage is great, but it also forces his linemates to hold onto the puck more. Hughes is someone who might benefit from playing with a power forward type, but mostly, he needs to get better at finding seams for his line-mates to get it back to him. You see a lot of one and done o-zone possessions when he's on the ice. He's got the escapability and the hands to play a better game along the boards. Again, this is another facet of the game that requires him to just get physically more mature. But I also think a part of a center's development is learning when to mitigate risk and play a very boring, support style depending on what happens on the ice.
The good news is these things are the biggest wake up call for every kid coming up as a center in the NHL. Maturity from an 18-year old is great, and Kakko should be applauded for how well-rounded he is. But I look at what's superlative, what it is that I can't find elsewhere. Right now, Hughes has the best edges and skating of anyone on the US team and better than most of the players in the NHL. Being able to make plays in all directions, at all times at any speed is not a minor advantage. And I'd put his hands + vision on par with Kane, Gaudreau and Eichel. Right now. This kid is speed incarnate and luckily his talent lies in the things that will save him from being physically punished at the NHL level. Sometimes some talents or facets of a player are of such a great magnitude that the rest does not matter.