What risk? I am curious.
He is 5.11 but what red flags you with him except his size
Stanley Cup winners are usually signficantly larger than other teams and the league is full of smaller players who just can't get it done in the playoffs. I am a firm believer in acquiring assets that will help win Stanley Cups and am not interested in using premium draft picks or trading premium assets for anything less than core pieces for a championship team. There are plenty of examples of smaller players who have been great in the playoffs, including recent examples such as Point and Marchessault but they are outliers.
Most smaller CHL scoring stars will fail due to their size disadvantage and this has clearly been shown for a long time. I do see some special qualities in Catton but I am not confident that he will be a difference maker in the NHL playoffs. This is not to assert that I do not believe in him either, I have just seen far more examples of his particular archetype fail in the playoffs than I have seen succeed and therein lies the risk of using a top ten pick on him.
If Hughes and his scouts do their due diligence and select him then I will be all in as there is a lot to love about this kid's game. I have been pumping Helenius' tires as well and he is also a little undersized but he is significantly stronger and much more physical than Catton.
So many interesting options and if Catton is your guy then so be it as he is very intriguing and would be easy to get behind. If we don't win the lottery and get Celebrini I don't have a clear dog in the race for our selection as there are too many acceptable options who each have their own strengths and weaknesses.