I think I'd be ok with that. He has too much upside to ignore.
That said, can you imagine Barzal and Cullen together? The blind behind-the-back turnovers.
Cullen is an interesting one to me. He was 5'8" not too long ago and whatever he's done in the past year+ has to be viewed in the context of if being accomplished during a huge growth spurt. Once he settles in at his final height and starts filling out, with his talent he could end up being one of the best players to come out of the draft - or he could bust. Definitely a dice-roll to some extent. I'd almost put Hemming and Belchetz in a similar dice roll category. And Lin with his size concerns but undeniable talent. Lawrence too, but I don't want him to be the pick.
Then you have the guys who seem to be "safer" picks, but who you hope maybe have some upside too. I'll put Novotny, Suvanto, Command, even Pugachyov, in that category. If they don't become great, they seem like they'll be contributing NHLers. With one pick in the first three rounds, there's some incentive not to "miss".
BTW, I'm leaving guys like Bjorck and Gustafsson out of this since I don't think they'll be available at #13, but if they are they're my pick with no second thoughts.
A couple of random comments. I saw one commentator compare Daxon Rudolph to Dobson, so he's on my "do not draft" list.

And Shcherbakov has his own category. I only really became aware of him when HockeyProspect ranked him at #14, and then I watched his videos and was super impressed with his level of skating and skill for a 6'5" defenseman. I read something else saying he's absolutely not physical and questioning if he'd always be as skinny as he is now. So definite concerns, but I watch his video and he looks like a top 10 talent.