Hmm this one is a little difficult. Depending on how you interpret or change the question, you can legitimately change the order of the players mentioned. For me personally something like:
Prime/peak/career individual: Karlsson, Hedman, Doughty
Career overall/who would I want to put in my team to win the cup with: Hedman, Doughty, Karlsson (ie: Actual accolades).
And to be a little more fair, Karlsson hasn't been the same since that skate cut. Without that, he might have had a chance to blow both Hedman and Doughty completely out of the water. It's really close though.