I was one of the biggest defenders of Ericsson back then but honestly he's even exceeded my expectations.
I figured his top end would be a solid middle pairing guy. And even that would've been a great return on their asset by the Red Wings given he's a dead last draft pick.
E has stepped up his physical game in front of the net, he's got the great first pass (including the occasional Rafalski long bombs), and most importantly he's become very poised in the defensive end.
I never saw it coming. But considering hindsight is 20/20, it makes you wonder if being a forward all those years ago helped him get to the next level? Most defensemen who are his size and taken late in the draft have skating issues. Ericsson skates pretty well. With his size and ability to skate he's got all the tools, he just needed to learn positioning and decision making. But those are teachable. Try teaching someone like Hal Gill to skate like Ericsson.
I guess what I'm trying to say is, Ericsson probably looked terrible when he was draft age because he hadn't been playing defense long and his decision making and positioning were likely lacking. But if you looked at it from a "he's huge and can skate" angle, and assumed the other assets would come with experience, then it's not really a surprise that he's as good as he is.