OEL, when he's fully engaged, can play a superior two-way role. He has great offensive instincts, and yet he can still motor back to cut off breakaways and pin down the opposing offense. He's at worst a 3/4D, even at his age... when he buys in to what's going on.
The problem with OEL is keeping his attention. For whatever reason, he's been playing unmotivated, and it shows on the ice. The trade to VAN will likely energize him for at least a season or two, and you're going to absolutely love him during that time. What happens afterward is anyone's guess - which is why we traded him, because five or so years of uncertainty at that price point was too big of a gamble.
I think Canucks fans ought to be cautiously optimistic. A fresh start will do OEL a world of good. I think he'll be a good piece for you.