I would say that you have to take the deal as you get the best player here in Doughty, who is arguably a top 5 D or so in the league. You are giving up mostly depth guys, the 3rd best players you have at these positions on your team, who most likely top out in the 60s, points wise.
Berglund, if he ever hits his potential, should outproduce any of the players you gave up. Stewart may be the guy you miss the most, because of the peripherals he contributes, but, that depends on the settings of your league.
You also stated that you need to make room for your draft picks. I don't see how you don't make out like a bandit here. Take the deal and thank your fellow GM when you kick his ass in this league.