Grigorenko has all the talent to be very, very good. Unfortunately something is missing. I think he's a hockey Jamarcus Russell. I would take a flyer on him for a low pick- like 5th round.
I'll admit I haven't watched him enough and I don't know what you think is missing.
But any big 21 year old who produces like he has the last couple years is going to be worth a lot more than a 5th rounder.
Would you trade William Karlsson for a 5th rounder? Because Grigo, despite being a good bit younger, has double the scoring rate and better stats across the board.
Milano and Bjork should not be available either. We should be trying to ADD prospects, not just swap them.
I'm not proposing a one for one because I don't know these guys enough, though Grigorenko could very well be better than both. But my question is: How young do you want this team to be? You're either trading mature players for prospects or your trading prospects for prospects, and we're already the babies of the NHL.