I'd take Doughty and give Gus + Top 5 Pick.
Detroit is not exactly going to be a powerhouse NHL team going-forward, IMO.... and who knows what Gustavsson's future will be like.
You probably lose this trade if that pick is #1.
If the pick is #2... it might be close to even.
If the pick is #3/#4/#5, you probably win this trade.
I'd go with the percentages... and make the deal.