Size is the first thing you notice about a player whether you see him on the ice or a spreadsheet but it says nothing about a player's will to battle. A 6'5 Pierre Engvall will lose every battle to a 5'11 gamer. Still, I think size (height, we mean height. Few players drafted now will play at the same weight three years from now) can be very important depending on your position.
I think you would absolutely prefer to have tall defenders, both on defence and at centre because of their wingspan and stick length and how they can use them to limit an opposition's space. I was okay with them moving on from Sandin because of it. We already have Rielly and I wouldn't want too many of these types defencemen. From Colombus through Montreal through Tampa we've learned this lesson everytime we've been "goalied" while taking shots from the perimeter around their giants.
Still, I wouldn't care about how tall a winger is. The most important physical asset for a winger is speed. You want your wingers to be fast enough to get in on the forecheck, limit ice and lanes, and increase pressure. I'm hopeful Treliving thinks similarly and I was encouraged when I coupled his comments at his pressers with reviews of his drafts.